20xx數學建模美賽f題論文-資料下載頁

　　

【正文】 tem tends to find all the shortest path to the remaining points.3) Dijkstra is the algorithm mainly deal with the weight of each arc in the Graph.For detailed explanation, if we use the original algorithm of Dijkstra, we will face much dilemma.Let’s suppose there’s a refugee, he will find a shortest way, he knows the shortest walk to every other country, but he don’t know the destination of his trip. So he will take the risk of shortest walking from Syria to Iraq, even worse situation.Even if the shortest way is determined once ,that one guy says that from Turkey we take a train, then we take a Greek bus… at last the refugees all take the way to Germany, one million departure from Syria and one million land at Germany, it is ridiculous to see they just change their base.Furthermore, is there any reason why the refugees choose Germany than other places? Is that because German is fine? But will it be fine after the flood of massive refugees?That’ s all what algorithm Dijkstra never told us, and we should form a better solution. The Unstoppable Refugee Algorithm Factor introductionSo if we are to deal with the refugee problem , we should advance the algorithm based on the actual condition, including the refugee individuals, the countries situation, the current policy or other details. Then we summarize the following factors:1) The total resource capacity: It is the single measurement of the capacity of the nation.2) The political factor , related to the economy increment/decrement percentage factor and the government attitude factor , basic attitude factor , and control factor , matching the real time database.3) The staying cost , for the settlement cost of the refugee and the resource consummation of the country. Related to the total GDP ,population , and inflation rate factor 4) The passing cost, for the temporary stay cost in the nation, related to daily supplement cost and average retention days , Detailed description of URAThen we can summarize the array list of 32 countries by the Total Capacity, and give each vertex in Graph G their weight, so we upgrade the simplified network into a doubleweight Graph , in which the weight of arc explains the difficulty level of the path while the weight of vertex explains the total capacity of this country.And of course we know that the refugee can either stay in the country or just take the country as the transit station for other destination. But both the permanent settlement of the refugees and the temporary fewdays stay will cause problems and will consume the limited resources in the country, and the difference is the degree of resource decreasing and potential disturbance.So what we need to do is to determine a plan of refugee administration by which we can arrange most efficient refugees movement while settle more population, with reasonable utilization of the limited resource and tend to reduce the unfair of refugee assignment. Under that condition, we discussed and give an advanced algorithm for the typical situation:Take an assumption that there’s one refugee individual were ready for departure, and he have the variety choices of destination, and he choose the country which owned the most total capacity value, and find the shortest path to the country, during his trip ,he will travel through several other countries, and cause minor resource decrement to those countries, and finally he arrived to destination, which will pay a huge budget to support his living, and result in a major resource decrement to that country. Then the value of total capacity of the countries on his route decreased.And for second, third, or the 10000th, they will do the same thing, the difference lies that if the most popular country’ s total capacity fell so fast that it owns no more the most capacity, it will not be chosen, but still has the possibility to be the ‘service station’ in which refugees may go though.If one country’s max capacity reached, the country will not support any more refugees and will shut down the boundary. So the path through the country will not be available any more.For thousands of thousands of choice done , until there is no path to go, there will be one talented custom officer—of course the puter will suit that job—who will report a huge statistic list of how many refugees settled and how many just travel through in specific country. And that should be the most reasonable and efficient route choice. So we summarized the algorithm in the followings:1) Define a Graph , with the weighted adjacency matrix of paths named arc[i][j] stands for all paths information between 32 countries and valued vertex array list max[i] stands for capacity initialized. In this condition, i=j=32.2) Define the start vertex and set the value of vertex to 0, means no capacity in the country, they are the refugee source—Syria, Iraq, Morroco, Lybia, etc.3) Choose the start point based on the population percentage of refugees in route start position, according to 2015 statistic database. Choose the vertex that has the most capacity value to be the end point 4) Find a shortest path from to , the path should have several mid points , or no mid points. For the mid points, the capacity value subtract the cost of passby: . For the final point , , in which stands for stay cost. And , recording the total path length. Record the settlement and passengerby number.5) If , , means the max capacity of country(i) reached, and the country must shut down the boundary.6) Redo process(2),(3), (4), (5), if or for all possible integer i, , break and print all stastic. Means the model reached its maximum capacity.7 Result and Dynamics Assessment The dynamic URAThe algorithm is based on dynamic situation, and the destination will change based on the remaining capacity of the specific nation , so the result is dynamic when the population and the destination changesIf we take the test of 500,