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مطلوب مساعده ممن له خبره في تخطيط المصانع

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  1. [1]
    gayo1995
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    مطلوب مساعده ممن له خبره في تخطيط المصانع

    السلام عليكم ورحمه الله وبركاته

    انا طالب في الصف الثالث قسم هندسه الانتاج ولدي مشروع عن (تخطيط مصنع لصناعه الألياف الضوئيهoptical fibers )
    ولا أعرف من أين أبدأ العمل ولا ماهي متطلبات المشروع من الناحيه الاداريه وعددالعمال والورديات و المخازن وغيرها
    من يعرف المباديء الأساسيه لتخطيط المصانع وكيف أحصل علي البيانات اللازمه يتفضل مشكورا بالاجابه علي هذا الموضوع
    وأنا علي ثقه بالله تعالي أني سأجد علي منتداكم الموقر ما أحتاجه.........وشكرا جزيلا

  2. [2]
    محمد فوزى
    محمد فوزى غير متواجد حالياً
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    الصورة الرمزية محمد فوزى


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    وسام الشكر

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  3. [3]
    صناعي1
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    الصورة الرمزية صناعي1


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    هذا الكتاب باللغة العربية، مفيد جدا بإذن الله
    http://www.arab-eng.org/vb/t119438.html

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  4. [4]
    gayo1995
    gayo1995 غير متواجد حالياً
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    جزاكم الله خيرا علي مجهوداتكم الطيبه..........

    وجعله الله في ميزان حسناتكم


    وعلي تواصل دائم باذن الله علي هذا المنتدي الطيب

    ولكن من أين يمكنني الحصول علي معلومات تاريخيه historical data عن مبيعات وتصنيع الألياف الضوئيه في مصر......علما بأني دخلت علي
    موقع شركه السويدي للكابلات و هي أكبر مصنع لها في مصر ولم أستطع الحصول علي مثل هذه البيانات

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  5. [5]
    محمد فوزى
    محمد فوزى غير متواجد حالياً
    عضو شرف
    الصورة الرمزية محمد فوزى


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    Fiber-optic communication
    From Wikipedia, the free encyclopedia
    Jump to: navigation, search

    In fiber-optic communications, information is transmitted by sending light through optical fibers.Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber. The light forms an electromagnetic carrier wave that is modulated to carry information. First developed in the 1970s, fiber-optic communication systems have revolutionized the telecommunications industry and have played a major role in the advent of the Information Age. Because of its advantages over electrical transmission, optical fibers have largely replaced copper wire communications in core networks in the developed world.

    The process of communicating using fiber-optics involves the following basic steps: Creating the optical signal involving the use of a transmitter, relaying the signal along the fiber, ensuring that the signal does not become too distorted or weak, receiving the optical signal, and converting it into an electrical signal.

    *******s [hide]
    1 Applications
    2 History
    3 Technology
    3.1 Transmitters
    3.2 Receivers
    3.3 Fiber
    3.4 Amplifiers
    3.5 Wavelength-division multiplexing
    3.6 Bandwidth-distance product
    3.7 Dispersion
    3.8 Attenuation
    3.9 Transmission windows
    3.10 Regeneration
    3.11 Last mile
    4 Comparison with electrical transmission
    5 Governing standards
    6 See also
    7 References
    8 Notes
    9 External links



    [edit] Applications
    Optical fiber is used by many telecommunications companies to transmit telephone signals, Internet communication, and cable television signals. Due to much lower attenuation and interference, optical fiber has large advantages over existing copper wire in long-distance and high-demand applications. However, infrastructure development within cities was relatively difficult and time-consuming, and fiber-optic systems were complex and expensive to install and operate. Due to these difficulties, fiber-optic communication systems have primarily been installed in long-distance applications, where they can be used to their full transmission capacity, offsetting the increased cost. Since the year 2000, the prices for fiber-optic communications have dropped considerably. The price for rolling out fiber to the home has currently become more cost-effective than that of rolling out a copper based network. Prices have dropped to $850 per subscriber in the US and lower in countries like The Netherlands, where digging costs are low.

    Since 1990, when optical-amplification systems became commercially available, the telecommunications industry has laid a vast network of intercity and transoceanic fiber communication lines. By 2002, an intercontinental network of 250,000 km of submarine communications cable with a capacity of 2.56 Tb/s was completed, and although specific network capacities are privileged information, telecommunications investment reports indicate that network capacity has increased dramatically since 2002.


    [edit] History
    The need for reliable long-distance communication systems has existed since antiquity. Over time, the sophistication of these systems has gradually improved, from smoke signals to telegraphs and finally to the first coaxial cable, put into service in 1940. As these communication systems improved, certain fundamental limitations presented themselves. Electrical systems were limited by their small repeater spacing (the distance a signal can propagate before attenuation requires the signal to be amplified), and the bit rate of microwave systems was limited by their carrier frequency. In the second half of the twentieth century, it was realized that an optical carrier of information would have a significant advantage over the existing electrical and microwave carrier signals.

    In 1966 Kao and Hockham proposed optical fibers at STC Laboratories (STL), Harlow, when they showed that the losses of 1000 db/km in existing glass (compared to 5-10 db/km in coaxial cable) was due to contaminants, which could potentially be removed.[1]

    The development of lasers in the 1960s solved the first problem of a light source, further development of high-quality optical fiber was needed as a solution to the second. Optical fiber was finally developed in 1970 by Corning Glass Works with attenuation low enough for communication purposes (about 20dB/km), and at the same time GaAs semiconductor lasers were developed that were compact and therefore suitable for fiber-optic communication systems.

    After a period of intensive research from 1975 to 1980, the first commercial fiber-optic communication system was developed, which operated at a wavelength around 0.8 µm and used GaAs semiconductor lasers. This first generation system operated at a bit rate of 45 Mbit/s with repeater spacing of up to 10 km.

    On 22 April, 1977, General Telephone and Electronics sent the first live telephone traffic through fiber optics, at 6 Mbit/s, in Long Beach, California.

    The second generation of fiber-optic communication was developed for commercial use in the early 1980s, operated at 1.3 µm, and used InGaAsP semiconductor lasers. Although these systems were initially limited by dispersion, in 1981 the single-mode fiber was revealed to greatly improve system performance. By 1987, these systems were operating at bit rates of up to 1.7 Gb/s with repeater spacing up to 50 km.

    The first transatlantic telephone cable to use optical fiber was TAT-8, based on Desurvire optimized laser amplification technology. It went into operation in 1988.

    TAT-8 was developed as the first undersea fiber optic link between the United States and Europe. TAT-8 is more than 3,000 nautical miles (5,600 km) in length and was the first transatlantic cable to use optical fibers. It was designed to handle a mix of information. When inaugurated, it had an estimated lifetime in excess of 20 years. TAT-8 was the first of a new class of cables, even though it had already been used in long-distance land and short-distance undersea operations. Its installation was preceded by extensive deep-water experiments and trials conducted in the early 1980s to demonstrate the project's feasibility.

    Third-generation fiber-optic systems operated at 1.55 µm and had loss of about 0.2 dB/km. They achieved this despite earlier difficulties with pulse-spreading at that wavelength using conventional InGaAsP semiconductor lasers. Scientists overcame this difficulty by using dispersion-shifted fibers designed to have minimal dispersion at 1.55 µm or by limiting the laser spectrum to a single longitudinal mode. These developments eventually allowed 3rd generation systems to operate commercially at 2.5 Gbit/s with repeater spacing in excess of 100 km.

    The fourth generation of fiber-optic communication systems used optical amplification to reduce the need for repeaters and wavelength-division multiplexing to increase fiber capacity. These two improvements caused a revolution that resulted in the doubling of system capacity every 6 months starting in 1992 until a bit rate of 10 Tb/s was reached by 2001. Recently, bit-rates of up to 14 Tbit/s have been reached over a single 160 km line using optical amplifiers.

    The focus of development for the fifth generation of fiber-optic communications is on extending the wavelength range over which a WDM system can operate. The conventional wavelength window, known as the C band, covers the wavelength range 1.53-1.57 µm, and the new dry fiber has a low-loss window promising an extension of that range to 1.30 to 1.65 µm. Other developments include the concept of "optical solitons, " pulses that preserve their shape by counteracting the effects of dispersion with the nonlinear effects of the fiber by using pulses of a specific shape.

    In the late 1990s through 2000, the fiber optic communication industry became associated with the dot-com bubble. Industry promoters, and research companies such as KMI and RHK predicted vast increases in demand for communications bandwidth due to increased use of the Internet, and commercialization of various bandwidth-intensive consumer services, such as video on demand. Internet protocol data traffic was said to be increasing exponentially, and at a faster rate than integrated circuit complexity had increased under Moore's Law. From the bust of the dot-com bubble through 2006, however, the main trend in the industry has been consolidation of firms and offshoring of manufacturing to reduce costs.

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  6. [6]
    gayo1995
    gayo1995 غير متواجد حالياً
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    مشكوووووووووووووور علي مجهوداتك الطيبه

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  7. [7]
    brain storming
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    والله ياريت المساعده فى ايجاد كتاب تخطيط مصانع با اللغه العربيه
    وجزاكم الله خير الجزاء

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  8. [8]
    صناعي1
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    اقتباس المشاركة الأصلية كتبت بواسطة gayo1995 مشاهدة المشاركة
    جزاكم الله خيرا علي مجهوداتكم الطيبه..........

    وجعله الله في ميزان حسناتكم


    وعلي تواصل دائم باذن الله علي هذا المنتدي الطيب

    ولكن من أين يمكنني الحصول علي معلومات تاريخيه historical data عن مبيعات وتصنيع الألياف الضوئيه في مصر......علما بأني دخلت علي
    موقع شركه السويدي للكابلات و هي أكبر مصنع لها في مصر ولم أستطع الحصول علي مثل هذه البيانات
    ربما تستطيع الحصول على معلومات اجمالية عن حجم المبيعات من خلال البيانات المالية التي تكون عادة في التقرير السنوي لاعمال الشركة

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  9. [9]
    brain storming
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    الصورة الرمزية brain storming


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    جزاكم الله خير الجزاء
    وجعله فى ميزان حسناتكم

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  10. [10]
    medobibo441
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    شكلك كده انتاج المنصورة و دكتور حسن هيروقك

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