- For a network of n nodes, only n - 1 routes are necessary to connect all nodes; that is, the upper bound is n - 1, and the complexity is O(n). This compares favorably to the routes, or O(n2), that would be required to connect each node to every other node in a point-to-point network. For example, in a system with 10 destinations, the spoke-hub system requires only 9 routes to connect all destinations, while a true point-to-point system would require 45 routes.
- The small number of routes generally leads to more efficient use of transportation resources. For example, bus are more likely to travel at full capacity, and can often travel routes more than once a day.
- Complicated operations, such as package sorting and accounting, can be carried out at the hub, rather than at every node.
- Spokes are simple, and new ones can be created easily.
- Customers may find the network more intuitive. Scheduling is convenient for them since there are few routes, with frequent service.
- Because the model is centralized, day-to-day operations may be relatively inflexible. Changes at the hub, or even in a single route, could have unexpected consequences throughout the network. It may be difficult or impossible to handle occasional periods of high demand between two spokes.
- Route scheduling is complicated for the network operator. Scarce resources must be used carefully to avoid starving the hub. Careful traffic analysis and precise timing are required to keep the hub operating efficiently.
- The hub constitutes a bottleneck or single point of failure in the network. Total cargo capacity of the network is limited by the hub's capacity. Delays at the hub (caused, for example, by bad weather conditions) can result in delays throughout the network. Delays at a spoke can also affect the network.
- Cargo must pass through the hub before reaching its destination, requiring longer journeys than direct point-to-point trips. This trade-off may be desirable for freight, which can benefit from sorting and consolidating operations at the hub, but not for time-critical cargo and passengers.
Disadvantages of point to point transit model
Penang public transit faces the daunting challenge of creating strategies for policies, technologies, infrastructure, and business models that pave a path to the future. The challenge lies in creating strategies that lead to scalable solutions for meeting growth in demand, including strategies affecting the communication, navigation and transit oriented development.
TRANSIT ORIENTED DEVELOPMENT is the exciting new fast growing trend in creating vibrant, livable communities. Also known as Transit Oriented Design, or TOD, it is the creation of compact, walkable communities centered around high quality transit systems. This makes it possible to live a higher quality life without complete dependence on a car for mobility and survival.
The transit station should be modeled after the Rest & Service Areas (RSA) while the transit stop should be model after the lay by of North South Expressway. Not only it serve as a drop off and pick up point, it is also serve as a rest area with scenic view for leisure and recreational activities. Such activities around the transit station or the transit stop enlarge its scope from being a transit point to an enlivened public space in the city.
The following are except from the Transportation Demand Management Encyclopedia of Victoria Transport Policy Institute.
TDM strategies can help achieve many municipal goals, including reduced traffic and parking congestion, road and parking cost savings, household cost savings, support for more local development and efficient land use (reduced sprawl), improved mobility for non-drivers, improved community livability, improved public fitness and health. Because municipal governments represent the interests of local residents they tend to recognize the diverse benefits of TDM.
Municipal governments can support TDM implementation in the following ways:
- Learn about TDM and the role it can play in achieving local planning objectives.
- Encourage or require local Transportation Agencies and Businesses to implement TDM solutions when they are cost effective. Work to build partnerships with Community Organizations to support TDM implementation.
- Improve Nonmotorized Transportation, Public Transit Services, Ridesharing, Taxi Services and other local transportation services.
- Apply more Comprehensive Transport Planning, including Multi-Modal Level-of-Service Indicators when evaluating transportation improvements.
- Implement TDM strategies, such as Commute Trip Reduction programs for employees, and Special Event Transport Management when sponsoring events that attract crowds.
Best TDM Strategies
The following strategies are particularly suitable for implementation by community organizations. For more detailed information see the TDM Summary Table.
Access management increases coordination between roadway design and land use development patterns to improve transportation system performance, including reduced congestion and accidents, and improved accessibility.
There are various ways to address the security concerns of people using alternative modes such as walking, cycling, ridesharing and public transit.
Various policies and programs can help preserve the value of assets such as roadways and parking facilities.
Improved bicycle parking, storage and changing facilities support cycling.
There are various ways to improve the integration of bicycling and public transit travel, including improved cycling access and bicycle storage at transit stops and stations, and the ability to carry bikes on transit vehicles.
Bus Rapid Transit (BRT) systems provide high quality bus service on busy urban corridors.
Car-free planning strategies reduce automobile travel at particular times and places, and to create pedestrian oriented streets.
Change Management involves various techniques that help build support for innovation within organizations.
Increased density (number of people or employees located in an area) and clustering (locating related activities close together) tend to reduce travel distances and improve travel options.
Various commuter financial incentives can be used to encourage use of more efficient commute modes. These include parking cash out, travel allowance, transit benefits, and rideshare benefits. They are often provided as an alternative to subsidized employee parking.
Transportation price and market reforms can encourage more efficient transportation and support TDM objectives.
Various planning reforms can result in more comprehensive and accurate transportation decision-making. Current planning results in omissions and distortions that tend to overvalue automobile-oriented improvements and undervalue alternative solutions to transportation problems. More comprehensive planning is particularly important when evaluating TDM and alternative modes.
Improved roadway and pathway connectivity tends to improve accessibility and reduce vehicle travel distances.
Flexible design requirements to reflect community values.
Planning that deals with uncertainly by identifying solutions to potential future problems.
There are many ways to improve cycling conditions and encouraging cycling activity, including improved design and maintenance of cycling paths and lanes, improved bicycle parking and changing facilities, and user education and information, and encouragement programs.
Creating vibrant downtowns, business districts, urban villages and other accessible, mixed-use activity centers tends to support many TDM strategies.
Mobility management strategies can help improve transportation services during emergencies.
Commute Trip Reduction (CTR) programs provide encouragement, incentives and support for commuters to use alternative modes, alternative work hours, and other efficient transport options.
Freight Transport Management increases freight transportation efficiency by shifting improving the quality of efficient freight modes (such as rail and integrated distribution services), providing incentives to use the most efficient option for each type of delivery, increasing load factors, improving logistics, and reducing unnecessary shipping distances and volumes.
There are various ways to fund transport programs, some of which support TDM objectives by charging directly for vehicle use.
High Occupant Vehicle (HOV) priority strategies give priority to public transit vehicles, vanpools and carpools in traffic and parking.
Institutional reforms include various changes to transportation organizations’ policies and practices that support Transportation Demand Management.
Least Cost Planning refers to planning and investment reforms that support demand management implementation when overall cost effective. This tends to support TDM policies and programs.
Light Rail Transit (LRT) systems provide convenient local transit service on busy urban corridors.
Location Efficient Development consists of residential and commercial development located and designed to maximize accessibility and overall affordability. Location Efficient Mortgages recognize the household savings at such locations, increasing borrowing ability.
A Multi-modal Access Guide provides customized directions to a particular destination by various modes.
New Urbanism (also called Neotraditional Design) includes various design and development practices that create more accessible, walkable, multi-modal, and livable communities. People who live and work in such communities tend to drive less and rely more on alternative modes than in more automobile-dependent locations.
Nonmotorized facilities such as walkways, sidewalks and paths can be managed to reduce conflicts and improve user convenience and safety.
Nonmotorized planning can improve walking and cycling conditions, and encourage use of nonmotorized modes.
Improved operations and management can encourage more efficient use of existing roadways.
Park & Ride facilities are parking lots at transit stations and stops. They support ridesharing and public transit use.
Various management strategies can result in more efficient use of parking resources. These include sharing, regulating and pricing of parking facilities, more accurate requirements, use of off-site parking facilities, improved user information, and incentives to use alternative modes.
Parking pricing involves charging motorists directly for using parking facilities and services, which provides revenue and cost recovery, encourages more efficient use of parking facilities, reduces parking facility costs and land requirements, reduces vehicle traffic and encourages use of alternative modes.
Comprehensive menu of solutions to parking problems.
Improved pricing methods can reduce the transaction costs and increase the cost efficiency of road tolls, parking fees and mileage charges.
Principles for prioritizing transportation activities and investments.
There are various ways to encourage public transit ridership by improving service, reducing fares, increasing user convenience and information, providing incentives, and supporting marketing programs.
Ridesharing refers to carpooling and vanpooling. Rideshare programs include ridematching services (which help travelers find travel partners), and strategies that give rideshare vehicles priority in traffic and parking.
Changes in roadway design and management practices can encourage more efficient transportation by providing more space for walking, cycling, ridesharing and public transit.
School Transport Management programs encourage parents, students and staff to reduce automobile trips and use alternative modes when traveling to and from schools.
Sharing parking facilities among various users can increase efficiency and support various TDM strategies.
Shuttle services include circulating shuttle buses, demand response and other special mobility services, jitneys and free transit zones.
Small-wheeled vehicles include wheeled luggage, walkers, skates, scooters and handcarts.
Smart Growth involves various local and regional land use planning practices that create more accessible, multi-modal, efficient and livable communities. This tends to reduce driving and increase use of alternative modes.
Various planning, regulatory and fiscal reforms help create more efficient land use. These reforms can help correct existing practices that encourage automobile-dependent land use development patterns.
Special programs can help managed transportation efficiently during major events, construction projects and emergencies.
Reducing traffic speeds tends to improve walking and cycling conditions, increase safety, reduce air and noise pollution, encourage more compact development, and reduce total automobile travel.
Street reclaiming involves various strategies that increase community interaction on neighborhood streets.
Streetscaping involves various ways to redesign roadways (particularly urban arterials) to support more multi-modal transportation and create more attractive and accessible communities.
TDM can help achieve sustainable transport planning objectives.
Taxi service improvements can help support TDM.
TDM marketing programs and strategies investigate the types of transportation services people want, identify barriers to alternative modes, and promote use of efficient transport options.
Discusses various issues to consider when planning and implementing Transportation Demand Management programs.
This chapter discusses different types of transportation management programs, how they are organized and funded, and their role in implementing TDM strategies.
Tourist Transport Management involves various policies and programs that improve recreational travel options and reduce automobile traffic in resort areas.
Traffic Calming refers to various roadway design features intended to reduce traffic speeds and volumes.
There are many ways to improve public transit service quality, including increased service speed, frequency, convenience, comfort, user information, affordability and ease of access.
Transit Oriented Development (TOD) refers to residential and commercial districts located around a transit station or corridor with high quality service, with good walkability, parking management and other design features that facilitate transit use and maximize overall accessibility.
Transportation Management Associations (TMAs) are member-controlled organizations that provide transportation services in a particular area. They support implementation of many TDM strategies.
Transportation systems can be better designed and managed to accommodate all users, including people with disabilities and other special needs.
Vehicle use restrictions limit vehicle traffic at a particular time and place.
There are many ways to improve walking conditions and encourage pedestrian transportation, including improved design and maintenance of sidewalks, paths, crosswalks, and better user information.
There are many ways to encourage walking and cycling transport, including facility improvements, promotion campaigns, events, educational programs, and development of guides and other information materials.
Provide wayfinding improvements and other multi-modal navigation tools that offer guidance for walking, cycling, driving and public transit use.