الوسم: المواصلات

وسائل المواصلات

نتيجة للزيادة الملحوظة في عدد السكان في مـختلف الدول وكذلك الزيادة في العمران والسكن الذي توجب عليه زيادة المواصلات التي تسهم في توفير التواصل بين مختلف المناطق والمجالات مثل مجال التصدير والاستيراد وفي التنقل بين المناطق المختلفة لأداء مختلف الأعمال.

النقل البري. طول السكك الحديدية في العالم كله يتجاوز 1.2 مليون كيلومتر, لكنها في الفترة الأخيرة لا تنمو, بل تنكمش في بعض بلدان أوروبا الغربية وأمريكا الشمالية بسبب المنافسة لها من جانب وسائل النقل الأخرى. وعلى الع** تنمو بسرعة شبكة طرق السيارات وخطوط الأنابيب بصورة خاصة. وفي وقت واحد يتزايد حجم النقل بهذه الوسائل كما تتغير جغرافيتها. وقد أصبح شحن الصناديق ينتشر أكثر فأكثر.

وترجع الأهمية الخاصة للنقل البري في البلدان الاشتراكية الأوروبية والآسيوية إلى المساحة الشاسعة وتلاصق الحدود الجغرافية وفي كل من البلدان الاشتراكية تشكل جميع طرق المواصلات ووسائلها شبكة نقل موحدة, نظرا إلى أن هذه الطرق والقسم الأساسي من وسائل النقل تعتبر ملكا للدولة. وفي البلدان الرأسمالية أيضا نمت جميع أشكال النقل البري, لكن توزيعها أبعد ما يكون عن المساواة. أما في بلدان آسيا وأفريقيا وأمريكا اللاتينية فالنقل البري يختلف كثيرا عنه في البلدان المتقدمة. ففي معظمها لا تنتشر السكك الحديدية بالقدر الكافي, بل ولا وجود لها في بعض البلدان. ومعظم الطرق ترابية. وأسطول الشاحنات محدود جدا. ولا تزال البلدان النامية تستخدم على نطاق واسع وسائل النقل غير الميكانيكية كعربات الكارو والحمالين.

النقل المائي. يقوم النقل البحري أساسا بخدمة التجارة الدولية. ويلعب النقل البحري بالذات دورا مرموقا في العلاقات الدولية للدول. وفي بعض الدول تلعب دورا هاما نقليات ساحلية. وأهمية النقل البحري محدودة بالنسبة لنقل الأفراد على الرغم من رخص النقل البحري.

ويعتبر نقل الشاحنات السائلة كالبترول والمنتجات البترولية أهم أنواع النقل البحري. وفي السنوات الأخيرة ازداد أيضا نقل الشاحنات الجافة كالخامات الحديدية والفحم والحبوب والبو**يت والأخشاب وغيرها. وقد أثرت هذه التغيرات في تكوين الأسطول البحري. إذا ارتفعت فيه حصة السفن المتخصصة, وعلى الأخص ناقلات السوائل التي تختص بنصف الحمولة الإجمالية. كذلك فقد ظهرت السفن المتخصصة في نقل أكثر من صنف كناقلات السوائل والخامات.

أما النقل المائي الداخلي فهو يخدم أساسا أغراض التجارة الداخلية في بعض البلدان وكذلك قسما من التجارة الدولية.
وبين البلدان الرأسمالية تبرز الولايات المتحدة وبلدان أوروبا الغربية واليابان في مجال تطوير النقل البحري.

النقل الجوي. تتزايد أهمية هذه الوسيلة النقلية في نقل الركاب والشاحنات الثمينة والمعرضة للتلف السريع. وقد وصل التعداد السنوي لركاب الطائرات ما يزيد عن 600 مليون نسمة. وتختص البلدان الاشتراكية بحصة كبيرة من الشبكات الدولية للنقل الجوي.

العلاقات الاقتصادية الدولية. من أهم أشكال العلاقات الاقتصادية الدولية التجارة الخارجية والعلاقات القرضية المالية وتبادل المعلومات العلمية التكنيكية وما يسمى بالصادرات (غير المنظورة) كتقديم مختلف الخدمات, مثل خدمة السفن الأجنبية الراسية في الموانئ وغيرها. كما أخذت السياحة في الفترة الأخيرة تلعب دورا مرموقا في العلاقات الدولية فعلى حين بلغ عدد المشتركين في السياحة الدولية 25 مليون نسمة.

تصدير رؤوس الأموال واحد من أهم أشكال العلاقات الاقتصادية الدولية المميزة للإمبريالية. ويتم استثمار رؤوس الأموال في الخارج من قبل الحكومات أو عن طريق شركات احتكارية معينة.
وعموما فإن جغرافيا العلاقات الاقتصادية الدولية بين البلدان الرأسمالية تع** علاقات صراع المنافسة الدائم من اجل أسواق التصريف ومصادر الخامات ومجالات الاستثمار والسيطرة الاقتصادية لدول الإمبريالية الكبرى.

والى جانب العلاقات الاقتصادية في إطار كل من النظامين الاقتصاديين العالميين توجد أيضا علاقات بين البلدان الاشتراكية والرأسمالية. وهي علاقات واسعة إلى حد كبير وآخذة في الاتساع المطرد. وتسعى البلدان الاشتراكية دوما إلى مواصلة تنمية هذه العلاقات على أساس مبادئ التعايش السلمي.

فالمواصلات عنصر أساسي ومهم في جميع الدول لما له من دور في تسهيل التنقل بين المناطق المختلفة لإنجاز مـختلف الأعمال وكذلك مهم في مجال تبادل السلع والخدمات وفي العديد من المجالات, وبتطور العالم وازدياد عددالسكان تزداد الحاجة إلى وسائل مواصلات أكثر حداثة وتطور من سابقاتها لتواكب التطور في المجتمع.

The Ximen station, one of the stations of Metro Taipei.
The Mumbai-Pune Expressway in India Transport or transportation is the movement of people and goods from one place to another. The term is derived from the Latin trans ("across") and portare ("to carry"). Industries which have the business of providing equipment, actual transport, transport of people or goods and services used in transport of goods or people make up a large broad and important sector of most national economies, and are collectively referred to as transport industries.

Transport

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For other uses, see Transport (disambiguation).
"Transportation" redirects here. For other uses, see Transportation (disambiguation).

The Ximen station, one of the stations of Metro Taipei.
The Mumbai-Pune Expressway in India Transport or transportation is the movement of people and goods from one place to another. The term is derived from the Latin trans ("across") and portare ("to carry"). Industries which have the business of providing equipment, actual transport, transport of people or goods and services used in transport of goods or people make up a large broad and important sector of most national economies, and are collectively referred to as transport industries.

[show]
1 Aspects of transport
2 Modes and categories
3 Transport and communications
4 Transport and land use
5 Transport in cities
6 Transport, energy, and the environment
7 Research
8 See also
9 Footnotes
10 References

Aspects of transport
The field of transport has several aspects: loosely they can be divided into a triad of infrastructure, vehicles, and operations. Infrastructure includes the transport networks (roads, railways, airways, waterways, canals, pipelines, etc.) that are used, as well as the nodes or terminals (such as airports, railway stations, bus stations and seaports). The vehicles generally ride on the networks, such as automobiles, bicycles, buses, trains, aircraft. The operations deal with the way the vehicles are operated on the network and the procedures set for this purpose including the legal environment (Laws, Codes, Regulations, etc.) Policies, such as how to finance the system (for example, the use of tolls or gasoline taxes) may be considered part of the operations.

Broadly speaking, the design of networks are the domain of civil engineering and urban planning, the design of vehicles of mechanical engineering and specialized subfields such as nautical engineering and aerospace engineering, and the operations are usually specialized, though might appropriately belong to operations research or systems engineering.

The current term also embraces aircraft with folding the wings that are intended to fold when on the ground. This is usually to ease storage or facilitate transport on, for example, a vehicle trailer or the powered lift connecting the hangar deck of an aircraft carrier to its flight deck. It also embraces aircraft, such as the General Dynamics F-111, Grumman F-14 Tomcat and the Pan via Tornado, which can vary the sweep angle of their wings during flight. These aircraft are termed "variable geometry" aircraft. When the wings of these aircraft are fully swept, usually for high speed cruise, the trailing edges of their wings about the leading edges of their tail planes, giving an impression of a single delta wing if viewed in plan. There are also rare examples of aircraft which can vary the angle of incidence of their wings in flight, such the F-8 Crusader, which are also considered to be "fixed-wing".

Two necessities for all fixed-wing aircraft (as well as rotary-wing aircraft) are air flow over the wings for lifting of the aircraft, and an open area for landing. The majority of aircraft, however, also need an airport with the infrastructure to receive maintenance, restocking, refueling and for the loading and unloading of crew, cargo and/or passengers. While the vast majority of aircraft land and take off on land, some are capable of take off and landing on ice, snow and calm water.

Rail
Main article: Rail transport
Rail transport is the transport of passengers and goods along railways or railroads. A typical railway (or railroad) track consists of two parallel steel (or in older networks, iron) rails, generally anchored perpendicular to beams (termed sleepers or ties) of timber, concrete, or steel to maintain a consistent distance apart, or gauge. The rails and perpendicular beams are usually then placed on a foundation made of concrete or compressed earth and gravel in a bed of ballast to prevent the track from buckling (bending out of its original configuration) as the ground settles over time beneath and under the weight of the vehicles passing above. The vehicles traveling on the rails are arranged in a train; a series of individual powered or empowered vehicles linked together, displaying markers. These vehicles (referred to, in general, as cars, carriages or wagons) move with much less friction than on rubber tires on a paved road, and the locomotive that pulls the train tends to use energy far more efficiently as a result.

Aecia Express, an American high-speed passenger train In rail transport, a train consists of rail vehicles that move along guides to transport freight or passengers from one place to another. The guide way (permanent way) usually consists of conventional rail tracks, but might also be monorail or maglev. Propulsion for the train is provided by a separate locomotive, or from individual motors in self-propelled multiple units. Most trains are powered by diesel engines or by electricity supplied by trackside systems. Historically the steam engine was the dominant form of locomotive power through the mid-20th century, but other sources of power (such as horses, rope (or wire), gravity, pneumatics, or gas turbines) are possible.

Automobile
An automobile is a wheeled passenger vehicle that carries its own motor. Different types of automobiles include cars, buses, trucks, and vans. Some include motorcycles in the category, but cars are the most typical automobiles. As of 2022 there were 590 million passenger cars worldwide (roughly one car for every ten people), of which 170 million in the U.S. (roughly one car for every two people).

The automobile was thought of as an environmental improvement over horses when it was first introduced in the 1890s. Before its introduction, in New York City alone, more than 1,800 tons of manure had to be removed from the streets daily, although the manure was used as natural fertilizer for crops and to build top soil. In 2022, the automobile is recognized as one of the primary sources of world-wide air pollution and a cause of substantial noise pollution and adverse health effects.

English seldom uses the term watercraft to describe any specific individual object (and probably then only as an affectation): rather the term serves to unify the category that ranges from small boats to the largest ships, and also includes the diverse watercraft for which some term even more specific than ship or boat (e.g., canoe, kayak, raft, barge, jet ski) comes to mind first. (Some of these would even be considered at best questionable as examples of boats.)

Ship transport
Main article: Ship transport
Ship transport is the process of moving people, goods, etc. by barge, boat, ship or sailboat over a sea, ocean, lake, canal or river. This is frequently undertaken for purposes of commerce, recreation or military objectives.

A hybrid of ship transport and road transport is the historic horse-drawn boat. Hybrids of ship transport and air transport are kite surfing and parasailing.

The first craft were probably types of canoes cut out from tree trunks. The colonization of Australia by Indigenous Australians provides indirect but conclusive evidence for the latest date for the invention of ocean-going craft; land bridges linked southeast Asia through most of the Malay Archipelago but a strait had to be crossed to arrive at New Guinea, which was then linked to Australia. Ocean-going craft were required for the colonization to happen.

Interposal transport
Main article: Interposal transport
Interposal freight transport refers to the combination of multiple types of transportation for a single shipment, for instance a shipment in a container may start on a truck in China, travel in a cargo ship over the Pacific Ocean to a port city in the U.S., then travel by train to the East Coast, finally being delivered by a truck.

Transport and communications
Transport and communication are $$$$ substitutes and complements. Though it might be possible that sufficiently advanced communication could substitute for transport, one could telegraph, telephone, fax, or email a customer rather than visiting them in person, it has been found that those modes of communication in fact generate more total interactions, including interpersonal interactions. The growth in transport would be impossible without communication, which is vital for advanced transportation systems, from railroads which want to run trains in two directions on a single track, to air traffic control which requires knowing the ******** of aircraft in the sky. Thus, it has been found that the increase of one generally leads to more of the other.

Too much infrastructure and too much smoothing for maximum vehicle throughput means that in many cities there is too much traffic and many – if not all – of the negative impacts that come with it. It is only in recent years that traditional practices have started to be questioned in many places, and as a result of new types of analysis which bring in a much broader range of skills than those traditionally relied on – spanning such areas as environmental impact analysis, public health, sociologists as well as economists who increasingly are questioning the viability of the old mobility solutions. European cities are leading this transition.

Efficiency
See also: Fuel efficiency in transportation
Another strategy is to make vehicles more efficient, which reduces pollution and waste by reducing the energy use. Electric vehicles use efficient electric motors, but their range is limited by either the extent of the electric transmission system or by the storage capacity of batteries. Electrified public transport generally uses overhead wires or third rails to transmit electricity to vehicles, and is used for $$$$ rail and bus transport. Battery electric vehicles store their electric fuel onboard in a battery pack. Another method is to generate energy using fuel cells, which may eventually be two to five times as efficient as the internal combustion engines currently used in most vehicles. Another effective method is to streamline ground vehicles, which spend up to 75% of their energy on air-resistance, and to reduce their weight. Regenerative braking is possible in all electric vehicles and recaptures the energy normally lost to braking, and is becoming common in rail vehicles. In internal combustion automobiles and buses, regenerative braking is not possible, unless electric vehicle components are also a part of the power train, these are called hybrid electric vehicles.

Walking and bicycling instead of traveling by motorized means also reduces the consumption of fossil fuels. While the use of these two modes generally declines as a given area becomes wealthier, there are some countries (including Denmark, Netherlands, Japan and parts of Germany, Finland and Belgium) where bicycling comprises a significant share of trips. Some cities with particularly high modal shares of cycling are Oulu (25%), Copenhagen (33%) and Groningen (50%). A number of other cities, including London, Paris, New York, Sydney, Bogotá, Chicago and San Francisco are creating networks of bicycle lanes and bicycle paths

There is also a growing movement of drivers who practice ways to increase their MPG and save fuel through driving techniques. They are often referred to as hyper milers. Hyper milers have broken records of fuel efficiency, averaging 109 miles per gallon driving a Prius. In non-hybrid vehicles these techniques are also beneficial. Hyper miler Wayne Girdles can get 59 MPG in a Honda Accord and 30 MPG in an
Acura MDX.