বুদ্ধিভিত্তিক প্রতারক

বুদ্ধিভিত্তিক প্রতারক বনাম সুন্দরবন।

ছবির উপরের বাম পাশ হইতে বয়ান শুরু করিলাম

১ম ও ২য় জন আন্দোলনের সাথে ফাকিস্তানি আতাত নয়, ফিন্দুস্তানী বন্ধুতায় গদগদ। তার পরের জনতো  সকল কে জিপিএ ৫ দিয়ে দিয়েছেন। এখন তিনি হইয়াছেন ইউএফও ফোপর ইকবাল। পরের জন খ্যতি অর্জন করেছিলেন ১/১১ সময় বর্তমানে তিনি মাননীয় প্রধানমন্ত্রীর ঘনিষ্টজনের দাবীদার। পরের দুইজন সম্পর্কে আমি অজ্ঞাত তাই বয়ান হইতে বিরত রইলাম। পরের দুজনের বয়ান নাইবা করিলাম। তাহার পরের জন জুসে বেহুস হইয়া দাদালামি করিতেছেন আর বুয়েট ফেরত জনতো জানেন না কয়লা কি জিনিস খায় না মাথায় দেয়, বর্তমানে তিনি পানি বিশুদ্ধ করনের প্রচার করিতেছেন বাহে। এইজন কহিলেও কহিতে পারেন কিন্তু কহিতে চাহেন না পাছে দাদাদের দেওয়া পদ্মতোষন খেতাব ছাড়তে হয়।  আরেব্বাস খাইছে আমারে, কেঠায় এইডা, এই মিয়াতো অহন পরবাসী, হেও আবার কইলাম বিলাত, ফাকিস্তানি মেয়রের অধীনে বইয়া আরামে আরবগো নাম কেমতে করে সেই ইতিহাস লেহন লাগছেন। দেখেছেন সবাই কত ব্যস্ত আর আপনারা শুধুশুধুু হেতেগরে সুন্দরবনের কাদায় নামাইতাছেন!

এবার প্রাসংগিক কথা বলি..  

আশাকরি সবাই জানেন যে, এই ব্যক্তি বর্গের প্রত্যেকেই প্রায় বংগবন্ধু শেখ মুজিবরের রাজনীতি দেখেছেন তার শাসন দেখেছেন আর এদের উদ্দেশেই তিনি বলেছিলেন "আমি চোরের খনি পেয়েছি"। স্বাধীনতার পর বংগবন্ধু সচেষ্ট ছিলেন ভারতীয় সেনা বিতাড়নে এবং তিনি ভারত সরকারের সরাসরি নিষেধ সত্তেও যোগ দিয়েছিলেন পাকিস্তানে আয়োজিত ও. আই. সি সম্মেলনে, এমন স্বাধীনচেতা বাংলাদেশীর অনুসারী আমরা কখনই কারো মুখাপেক্ষী নই। উনারা না হয় বিদেশ বিভূইয়ে আপন বসতি গড়ে নেবেন কিন্তু আমি আপনি কি করব যদি সুন্দরবন না থাকে? এই দেশ না থাকে?

 সবশেষে একটি প্রস্তাব রাখি - 

১। এই প্রকল্পের জন্য সম্মিলিতভাবে ফারাক্কার কাছাকাছি কোন জায়গা  নির্ধারন করতে পারি।

২। এর ফলে দিনাজপুরের কয়লা আমরা ব্যাবহার করতে পারব এবং ভারত তার নদীপথ ব্যবহার করে কয়লা আনতে পারবে। 

৩। আমাদের উত্তর এলাকার লোক গুলোর কিছু জীবিকার ব্যাবস্থা হবে

৪। উত্তর এলাকার স্থল বন্দর গুলো চালু হবে এবং তাদের অর্থনীতি উন্নয়নে ভুমিকা রাখবে।

৫। সর্বোপরি সুন্দরবন রক্ষা পাবে।

Pablo Picasso

"Bad artists copy. Good artists steal."

 

The purpose of art is washing the dust of daily life off our souls.”

The chief enemy of creativity is 'good' sense.”

It takes a long time to become young.”

Our goals can only be reached through a vehicle of a plan, in which we must fervently believe, and upon which we must vigorously act. There is no other route to success.”

The older you get the stronger the wind gets - and it's always in your face.”

Give me a museum and I'll fill it.”

The world today doesn't make sense, so why should I paint pictures that do? ”

It is your work in life that is the ultimate seduction.”

Art is not the application of a canon of beauty but what the instinct and the brain can conceive beyond any canon. When we love a woman we don't start measuring her limbs. ”

Bad artists copy. Good artists steal. ”

Everything you can imagine is real. ”

Art is the elimination of the unnecessary. ”

Action is the foundational key to all success.”

All children are artists. The problem is how to remain an artist once he grows up. ”

An idea is a point of departure and no more. As soon as you elaborate it, it becomes transformed by thought. ”

Art is not the application of a canon of beauty but what the instinct and the brain can conceive beyond any canon. When we love a woman we don't start measuring her limbs. ”

Colors, like features, follow the changes of the emotions. ”

Everything is a miracle. It is a miracle that one does not dissolve in one's bath like a lump of sugar. ”

He can who thinks he can, and he can't who thinks he can't. This is an inexorable, indisputable law. ”

I don't believe in accidents. There are only encounters in history. There are no accidents. ”

It took me four years to paint like Raphael, but a lifetime to paint like a child. ”

Every act of creation is first an act of destruction. ”

I do not seek. I find. ”

There is no abstract art. You must always start with something. Afterward you can remove all traces of reality. ”

I paint objects as I think them, not as I see them. ”

Art is a lie that makes us realize the truth”

Every positive value has its price in negative terms... the genius of Einstein leads to Hiroshima.”

He can who thinks he can, and he can't who thinks he can't. This is an inexorable, indisputable law.”

All children are artists. The problem is how to remain an artist once he grows up.”

Painting is a blind man's profession. He paints not what he sees, but what he feels, what he tells himself about what he has seen.”

Youth has no age.”

Others have seen what is and asked why. I have seen what could be and asked why not.”

Love is the greatest refreshment in life.”

To draw you must close your eyes and sing.”

I begin with an idea and then it becomes something else.”

I'd like to live as a poor man with lots of money.”

It is your work in life that is the ultimate seduction.”

The hidden harmony is better than the obvious.”

We don't grow older, we grow riper.”

You mustn't always believe what I say. Questions tempt you to tell lies, particularly when there is no answer.”

There are only two types of women - goddesses and doormats.”

It is your work in life that is the ultimate seduction.”

The chief enemy of creativity is 'good' sense.”

Computers are useless. They can only give you answers.”

When I was a child, my mother said to me, 'If you become a soldier, you'll be a general. If you become a monk, you'll end up as the Pope.' Instead, I became a painter and wound up as Picasso.”

To make oneself hated is more difficult than to make oneself loved.”

Others have seen what is and asked why. I have seen what could be and asked why not.”

www.pablopicasso.org/ 

Branding & Design

Branding & Design

Primitive people markup their emotional touch in the cave and that was the first BRANDING idea. That Art is establishing a glorious mark of their life of view which means living in heart with meaningful prosperity. Purple Propeller work on it for you and your sign of MODESTY.

www.purplepro.biz 

Wireless Communication

Wireless Communication

Wireless communication uses radio frequencies (RF) or infrared (IR) waves to transmit data between devices on a LAN. For wireless LANs, a key component is the wireless hub, or access point, used for signal distribution.

Figure 1.1:Wireless Network

To receive the signals from the access point, a PC or laptop must install a wireless adapter card (wireless NIC). Wireless signals are electromagnetic waves that can travel through the vacuum of outer space and through a medium such as air. Therefore, no physical medium is necessary for wireless signals, making them a very versatile way to build a network. Wireless signals use portions of the RF spectrum to transmit voice, video, and data. Wireless frequencies range from 3 kilohertz (kHz) to 300 gigahertz (GHz). The data-transmission rates range from 9 kilobits per second (kbps) to as high as 54 Mbps. The primary difference between electromagnetic waves is their frequency. Low-frequency electromagnetic waves have a long wavelength (the distance from one peak to the next on the sine wave), while high-frequency electromagnetic waves have a short wavelength.

Some common applications of wireless data communication include the following:

• Accessing the Internet using a cellular phone

• Establishing a home or business Internet connection over satellite

• Beaming data between two hand-held computing devices

• Using a wireless keyboard and mouse for the PC

Another common application of wireless data communication is the wireless LAN (WLAN), which is built in accordance with Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards. WLANs typically use radio waves (for example, 902 megahertz [MHz]), microwaves (for example, 2.4 GHz), and IR waves (for example, 820 nanometers [nm]) for communication. Wireless technologies are a crucial part of the today’s networking. See Chapter 28, “Wireless LANs,” for a more detailed discuss on wireless networking.

Comparing Media Types

Presented in Table 1.1 are comparisons of the features of the common network media. This chart provides an overview of various media that you can use as a reference. The medium is possibly the single most important long-term investment made in a network. The choice of media type will affect the type of NICs installed, the speed of the network, and the capability of the network to meet future needs.

Table 1.1 Media Type Comparison

Media Type	Maximum Segment Length	Speed	Cost	Advantages	Disadvantages
UTP	100 m	10 Mbps to 1000 Mbps	Least expensive	Easy to install; widely available and widely used	Susceptible to interference; can cover only a limited distance
STP			More expensive than UTP	Reduced crosstalk; more resistant to EMI than Thinnet or UTP	Difficult to work with; can cover only a limited distance
Coaxial	500 m (Thicknet) 185 m (Thinnet)	10 Mbps to 100 Mbps	Relatively inexpensive, but more costly than UTP	Less susceptible to EMI interference than other types of copper media	Difficult to work with (Thicknet); limited bandwidth; limited application (Thinnet); damage to cable can bring down entire network
Fiber-Optic	10 km and farther (single mode) 2 km and farther (multimode)	100 Mbps to 100 Gbps (single mode) 100 Mbps to 9.92 Gbps (multimode)	Expensive	Cannot be tapped, so security is better; can be used over great distances; is not susceptible to EMI; has a higher data rate than coaxial and twisted-pair cable	Difficult to terminate

Summary:

• Coaxial cable consists of a hollow outer cylindrical conductor that surrounds a single inner wire conductor.

• UTP cable is a four-pair wire medium used in a variety of networks.

• STP cable combines the techniques of shielding, cancellation, and wire twisting.

• Fiber-optic cable is a networking medium capable of conducting modulated light transmission.

• Wireless signals are electromagnetic waves that can travel through the vacuum of outer space and through a medium such as air.

Coaxial Cable

Coaxial Cable

Coaxial cable consists of a hollow outer cylindrical conductor that surrounds a single inner wire made of two conducting elements. One of these elements, located in the center of the cable, is a copper conductor. Surrounding the copper conductor is a layer of flexible insulation. Over this insulating material is a woven copper braid or metallic foil that acts both as the second wire in the circuit and as a shield for the inner conductor. This second layer, or shield, can help reduce the amount of outside interference. Covering this shield is the cable jacket (See Figure 1.1)

Figure 1.1 Coaxial Cable (

Coaxial cable supports 10 to 100 Mbps and is relatively inexpensive, although it is more costly than UTP on a per-unit length. However, coaxial cable can be cheaper for a physical bus topology because less cable will be needed. Coaxial cable can be cabled over longer distances than twisted-pair cable. For example, Ethernet can run approximately 100 meters (328 feet) using twisted-pair cabling. Using coaxial cable increases this distance to 500m (1640.4 feet). For LANs, coaxial cable offers several advantages. It can be run with fewer boosts from repeaters for longer distances between network nodes than either STP or UTP cable. Repeaters regenerate the signals in a network so that they can cover greater distances. Coaxial cable is less expensive than fiber-optic cable, and the technology is well known; it has been used for many years for all types of data communication.

When working with cable, you need to consider its size. As the thickness, or diameter, of the cable increases, so does the difficulty in working with it. Many times cable must be pulled through existing conduits and troughs that are limited in size. Coaxial cable comes in a variety of sizes. The largest diameter (1 centimeter [cm]) was specified for use as Ethernet backbone cable because historically it had greater transmission length and noise-rejection characteristics. This type of coaxial cable is frequently referred to as Thicknet. As its nickname suggests, Thicknet cable can be too rigid to install easily in some situations because of its thickness. The general rule is that the more difficult the network medium is to install, the more expensive it is to install. Coaxial cable is more expensive to install than twisted-pair cable. Thicknet cable is almost never used except for special-purpose installations. A connection device known as a vampire tap was used to connect network devices to Thicknet. The vampire tap then was connected to the computers via a more flexible cable called the attachment unit interface (AUI). Although this 15-pin cable was still thick and tricky to terminate, it was much easier to work with than Thicknet. In the past, coaxial cable with an outside diameter of only 0.35 cm (sometimes referred to as Thinnet) was used in Ethernet networks. Thinnet was especially useful for cable installations that required the cable to make many twists and turns. Because it was easier to install, it was also cheaper to install. Thus, it was sometimes referred to as Cheapernet. However, because the outer copper or metallic braid in coaxial cable comprises half the electrical circuit, special care had to be taken to ensure that it was properly grounded. Grounding was done by ensuring that a solid electrical connection existed at both ends of the cable. Frequently, however, installers failed to properly ground the cable. As a result, poor shield connection was one of the biggest sources of connection problems in the installation of coaxial cable. Connection problems resulted in electrical noise, which interfered with signal transmittal on the networking medium. For this reason, despite its small diameter, Thinnet no longer is commonly used in Ethernet networks.

The most common connectors used with Thinnet are BNC, short for British Naval Connector or Bayonet Neill Concelman, connectors (see Figure 8-5). The basic BNC connector is a male type mounted at each end of a cable. This connector has a center pin connected to the center cable conductor and a metal tube connected to the outer cable shield. A rotating ring outside the tube locks the cable to any female connector. BNC T-connectors are female devices for connecting two cables to a network interface card (NIC). A BNC barrel connector facilitates connecting two cables together.

Figure 1.2 Thinnet and BNC Connector

The following summarizes the features of coaxial cables:

• Speed and throughput—10 to 100 Mbps

• Average cost per node—Inexpensive

• Media and connector size—Medium

• Maximum cable length—500 m (medium)

Plenum Cable

Plenum cable is the cable that runs in plenum spaces of a building. In building construction, a plenum (pronounced PLEH-nuhm, from Latin meaning “full”) is a separate space provided for air circulation for heating, ventilation, and air-conditioning (sometimes referred to as HVAC), typically in the space between the structural ceiling and a drop-down ceiling. In buildings with computer installations, the plenum space often is used to house connecting communication cables. Because ordinary cable introduces a toxic hazard in the event of fire, special plenum cabling is required in plenum areas. In the United States, typical plenum cable sizes are AWG sizes 22 and 24. Plenum cabling often is made of Teflon and is more expensive than ordinary cabling. Its outer material is more resistant to flames and, when burning, produces less smoke than ordinary cabling. Both twisted pair and coaxial cable are made in plenum cable versions.

Fiber-Optic Cable

Fiber-optic cable used for networking consists of two fibers encased in separate sheaths. If you were viewing it in a cross-section, you would see that each optical fiber is surrounded by layers of protective buffer material, usually a plastic shield, then a plastic such as Kevlar, and finally an outer jacket. The outer jacket provides protection for the entire cable, while the plastic conforms to appropriate fire and building codes. The Kevlar furnishes additional cushioning and protection for the fragile, hair-thin glass fibers (see Figure 8-6). Wherever buried fiber-optic cables are required by codes, a stainless-steel wire sometimes is included for added strength.

Figure 1.3 Fiber-Optic Cable

Figure 1.4 Fiber-Optic Cable

The light-guiding parts of an optical fiber are called the core and the cladding. The core is usually very pure glass with a high index of refraction. When a cladding layer of glass or plastic with a low index of refraction surrounds the core glass, light can be trapped in the fiber core. This process is called total internal reflection. It allows the optical fiber to act like a light pipe, guiding light for tremendous distances, even around bends. Fiber-optic cable is the most expensive but it supports line speeds of more than 1 Gbps.

Two types of fiber-optic cable exist:

• Single-mode—Single-mode fiber cable allows only one mode (or wavelength) of light to propagate through the fiber. It is capable of higher bandwidth and greater distances than multimode, and it is often used for campus backbones. This type of fiber uses lasers as the light-generating method. Single-mode cable is much more expensive than multimode cable. Its maximum cable length is more than 10 km (32808.4 feet).

Figure 1.4 Fiber-Optic Cable

• Multimode—Multimode fiber cable allows multiple modes of light to propagate through the fiber. It is often used for workgroup applications and intrabuilding applications such as risers. It uses light-emitting diodes (LEDs) as a light-generating device. The maximum cable length is 2 km (6561.7 feet). The characteristics of the different transport media have a significant impact on the speed of data transfer. Fiber-optic cable is a networking medium capable of conducting modulated light transmissions. Compared to other networking media, it is more expensive. However, it is not susceptible to EMI, and it is capable of higher data rates than any of the other types of networking media discussed in this chapter. Fiber-optic cable does not carry electrical impulses as other forms of networking media that use copper wire do. Instead, signals that represent bits are converted into beams of light.

NOTE- Even though light is an electromagnetic wave, light in fibers is not considered wireless because the electromagnetic waves are guided in the optical fiber. The term wireless is reserved for radiated, or unguided, electromagnetic waves.

Fiber-optic connectors come in single-mode and multimode varieties. The greatest difference between single-mode connectors and multimode connectors is the precision in the manufacturing process. The hole in the single-mode connector is slightly smaller than in the multimode connector. This ensures tighter tolerances in the assembly of the connector. The tighter tolerances make field assembly slightly more difficult. A number of different types of fiber-optic connectors are used in the communications industry. The following list briefly describes two of the commonly used connectors:

• SC—SC type connectors feature a push-pull connect and disconnect method. To make a connection, the connector is simply pushed into the receptacle. To disconnect, the connector is simply pulled out.

• ST—ST fiber-optic connector is a bayonet type of connector. The connector is fully inserted into the receptacle and is then twisted in a clockwise direction to lock it into place.

Figure 8-7 ST Fiber-Optic Connector

The following summarizes the features of fiber-optic cables:

• Speed and throughput   —More than 1 Gbps

• Average cost per node  —Expensive

• Media and connector size—Small

• Maximum cable length   —More than 10 km for single 

                                        mode; up to 2 km for multimode