Combinatorial optimization: Knapsack problem 2: Unterschied zwischen den Versionen

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     She has the choice between six different items which she can pack.  
 
     She has the choice between six different items which she can pack.  
 
     Each object has a special benefit c_i for the woman and a weight a_i.
 
     Each object has a special benefit c_i for the woman and a weight a_i.
     What items should be selected by her to have the maximum benefit without exceeding the maximum weight oft 25 kg?
+
     What items should be selected by her to have the maximum benefit without exceeding the maximum weight of 25 kg?
  
 
     [[Datei:Tabelle Wiki.jpg]]
 
     [[Datei:Tabelle Wiki.jpg]]
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     To apply the different methods a ranking must be formed first.  
 
     To apply the different methods a ranking must be formed first.  
 
      
 
      
     For this purpose, a quotient is formed from the weight a_i and the benefit c_i.
+
     For this purpose, a quotient is formed from the benefit c_i and the weight a_i.
 
     Afterwards, the values are sorted according to the size.
 
     Afterwards, the values are sorted according to the size.
  
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     Ordered list:
 
     Ordered list:
 
      
 
      
  [[Datei:Liste.jpg]]
+
    [[Datei:Liste.jpg]]
  
 
     This list is the basis for all applicable methods.
 
     This list is the basis for all applicable methods.
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     The goal is to obtain an integer solution. One begins with the object of rank 1, then rank 2 and so on  
 
     The goal is to obtain an integer solution. One begins with the object of rank 1, then rank 2 and so on  
     and sets the variable equal 1 or 0, until the maximum weight of 25 kg is reached.
+
     and sets the variable equal 1 or 0. The items can be taken as long as the maximum weight of 25 kg is reached.
 +
    This means that the last possible item mostly can't be taken completely.
 
     The solution with the higher objective function value is branched. If the objective function value is less  
 
     The solution with the higher objective function value is branched. If the objective function value is less  
 
     than the value that provides the best integer solution, this solution is not branched.
 
     than the value that provides the best integer solution, this solution is not branched.
 
+
   
 
     [[Datei:Kolesar.jpg]]     
 
     [[Datei:Kolesar.jpg]]     
  

Version vom 26. Juni 2013, 09:44 Uhr

Knappsack-Problem

1. Introduction

2. Application and definition

3. Example

   A woman wants to go on vacation. But now she has to overcome a serious problem, because the airline prescribe 
   a maximum weight of 25 kg (b = 25 kg)for her luggage (the worst that can happen to a woman).
   She has the choice between six different items which she can pack. 
   Each object has a special benefit c_i for the woman and a weight a_i.
   What items should be selected by her to have the maximum benefit without exceeding the maximum weight of 25 kg?
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden

4. Methods 1 - 3

   To apply the different methods a ranking must be formed first. 
   
   For this purpose, a quotient is formed from the benefit c_i and the weight a_i.
   Afterwards, the values are sorted according to the size.
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden
   Ordered list:
   
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden
   This list is the basis for all applicable methods.

   a) Kolesar
   The goal is to obtain an integer solution. One begins with the object of rank 1, then rank 2 and so on 
   and sets the variable equal 1 or 0. The items can be taken as long as the maximum weight of 25 kg is reached.
   This means that the last possible item mostly can't be taken completely.
   The solution with the higher objective function value is branched. If the objective function value is less 
   than the value that provides the best integer solution, this solution is not branched.
   
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden
   b) Greenberg & Hegerich
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden
   c) Cascading Tree
Fehler beim Erstellen des Vorschaubildes: Die Miniaturansicht konnte nicht am vorgesehenen Ort gespeichert werden

5. Method 4

6. complexity problem