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Adaptive Traffic Signal Control | New Way To Reduce Traffic

1. Introduction Urban areas are increasingly grappling with the problem of traffic congestion, which not only leads to longer travel times but also results in excessive fuel consumption and harmful emissions. With cities growing in both size and population, efficient traffic management has become a priority for city planners. One of the most promising solutions to address this challenge is Adaptive Traffic Signal Control (ATSC). By adjusting traffic light timings based on real-time data, ATSC significantly reduces delays and improves traffic flow, thus offering a smarter way to manage urban mobility. 2. What is Adaptive Traffic Signal Control? Adaptive Traffic Signal Control (ATSC) is an advanced traffic management system designed to optimize traffic light timings in response to real-time traffic conditions. Unlike traditional systems that operate based on fixed schedules, ATSC uses real-time data to dynamically adjust traffic signals. This results in fewer traffic jams, smoother vehic
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Principles of surveying


Principles of surveying


There are two basic principles of surveying. These are found useful in all stages of project.
1. To work from whole to part
2. To locate a point by at least two measurements

TO WORK FROM WHOLE TO PART

    
        The main idea of working from whole to part is to localise the errors and prevent their accumulation.
    
        You can also work with part to whole but in that case error from part will get accumulated and magnify significantly, thus until and unless there is no alternative available don't use part to whole.

        By working whole to part errors gets localise and will not transfer to whole project. We can take example as setting out intermediate points between A and B. While setting external points first and then moving inside to set intermediate point is a example of working whole to part; and setting out with intermediate points first and working towards external point is example of working part to whole.

1. Whole to part and 2. part to whole 

        Above figure shows figure 1. whole to part and Figure 2. part to whole, in which work is to set out points in line AB. Fig 1 shows setting external points A and B first and then going to set intermediate points C, D & E, etc. assuming surveyor got error in locating point C and located point C' with error 'ec' (CC') but due to whole to part principle used error got localise and only line AC' and C'D got wrong length while DE and EB is true length.

    But in fig 2. working part to whole, setting immediate intermediate points A and C and follow trough to setting points D, E and B, etc. but assume we got error in setting point C as C' and extending line AC' will lead to accumulation of errors in all the other points as DD', EE' and BB' also in increasing order.

        These is only one example of benefits of working with principle whole to part. 


TO LOCATE A POINT BY AT LEAST TWO MEASUREMENTS


        As a matter of fact no point can be located with locating by at least 3 measurements in 3 dimensional space, but for plane surveying at least 2 measurements are required to locate a point accurately. 

example, if we want to locate point C but we only know the distance BC so, point C can be anywhere on the circle from centre B with radius BC. Thus there is practically no way to accurately locate point  C with only one known measurement.

Measurements required to locate a point.

Plane case (2D), 
1. Distance, Distance
2. Distance, angle
3. Angle, angle

Let's see the figure given below.
1. Distance, distance
        Setting point C by known distances AC and BC.

2. Distance, Angle

        Working with distance and angle measurement is widely used technique, making angle 90' and working only with distance measurements using Pythagoras theorem is useful in setting out of survey points. 
  

3. Angle, angle

        When working only with angle is possible at obstructions like river crossing, valley, etc. locating a point can also be done by intersecting angle lines from two points.

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