Cities dealing with space structure analysis of Lorestan State ( Iran ) using entropy model at urban , province , township , district and national levels

The purpose of this article is to evaluate urban population distribution and number of cities distribution at the urban levels in one zone. By using this model, we can understand space balance rate of population settlement, and the number of cities at the urban system level, state, zone and country. By using entropy, coefficient model has been tried to understand the balance rate of population settlement and cities number at the urban, district, township system levels of Lorestan. So, dwellings and population general censuses’ results of 1986, 1996 and 2006 have been used to define changes and alterations of state dealing with space structure for the past 30 years. This study shows that there is unbalance trend to urban movement levels at space structure. There is less unbalance movement at township levels compared to the urban levels. States trend to the space organization balance at the national level.


INTRODUCTION
In academic world, it is believed that everybody has scientific education, especially in statistic and mathematics field, which are more reliable for social reality studies (Kalantari, 2008, p109).Size, dealing with space organization and urban hierarchical order has been a noticeable source for researcher for a long time.It is a subject that has been discussed by geographers for a long time.
Space organization and hierarchical order means cities classification according to their applied importance in that it represents different aspects of reciprocal actions between urban zones and relations between different parts of a hierarchical order system.There are different models for space organization analysis such as manufacture model of urban hierarchical profile, grade rule model, size and statistical models in geography science.
Entropy index coefficient model is one of these models that is used to analyze space organization or organizing space.In this article we want to analyze space structure Lorestan by studying its urban system, and by using entropy index model, we try to have an ideal analysis of space organization state in different period of census.That is how space organization was in 1986, 1996, 2006 and how it is now (2006) and how will it be in future?Is it going to be on a balance or unbalance routine?Do all urban levels (urban, town ship, district) have the same procedure?Or do they have individual reasonable results?Finally in Lorestan space organization, we tried to understand the effective factors of balance or unbalance of space organizing and to find the best solution (in unbalance case) (Figure 1 and 2).

Research questions
Space organizing of Lorestan cities includes alternative natural process by human.It leads to production of social condition and work division in organized system in the Lorestan State.In fact, space expansion and its distribution are not permanently stable at the state level.But, is also dependant on relatively conditions that are changeable over the time.The purpose of geography is to study these changes.
In this article, attempts have been made to answer the following questions and what can we do to make stability in this organization.Does the population distribution organization have similar process in state at the urban, township, district, levels or does everyone have special or independent process?
In which levels is the balance improving or which one has unbalance improvement?At the national levels, do provinces have unbalance procedure or balance procedure?
If entropy has trend of zero, it will show more centralization or increase of centralization or unbalance in population distribution between cities, and movement toward one or higher than shows unbalance distribution in zone level (Mousavi-Hekmatnia, 2006: 189-190).This index has been used for centralization degree definition or geographical phenomenon.Distribution separation in small districts is called centralization index (Tolaee, 1996: 225).
In this article we want to calculate population of cities, number of cities space distribution at urban, district, township of Lorestan State by using coefficient entropy and we consider using coefficient of entropy at the states of the country.

Napierian frequency and frequency analysis of urban space organization of Lorestan State by using coefficient of entropy
In this part of the research, we analyze cities of Lorestan by using coefficient of entropy.This research has used some variables such as population and some statistics such as general census of population and dwellings in three alternative periods of 1986, 1996, 2006.

Analysis of Lorestans cities space structure by using entropy coefficient of frequency and Napierian frequency
We want to study space existence process in cities of Lorestan State.To achieve better result, we use entropy coefficient model in Lorestans population space structure.We also want to understand how population is distributed in the Lorestans cities, and which procedure (balance, unbalance) is shown.
In this article, three alternative censuses of dwelling and population of Lorestan State in 1986, 1996, 2006 years were used (Tables 4 to 6).

Analysis of Lorestan , s district levels space organization by using of entropy coefficient of Napierian frequency and frequency
There are three natural geographical districts in Lorestan as follows: 1. High and elevated cities of Lorestan that are in some parts of North and east of Oshterinan Borojerd ,Dorod, Selseleh, Delfan, Azna and Aligodarz.2. Central city of Lorestan: Has a mild geographical situation.This city is Khorramabad.It has a geometrical centre and it is the official and political centre for Lorestan State.3. West and south cities have similar weather and structure with special unity, such as: Kohdasht and Poledokhtar.
In this article, we did space organization and structure analysis of Lorestan State by using population statistics of three consecutive populations and dwelling censuses in 1986, 1996, 2006 (Tables (Tables 7 to 9).Regarding the population space organization, we studied space existence producers using entropy coefficient model in the states of the country of Iran.In this part, three consecutively periods of dwelling and population censuses in Iran in 1986Iran in , 1996Iran in , 2006 years were used (Table 10).In these three periods, in 1986 country population space organization showed balance condition at state levels, as the entropy coefficient amount is close to one.It showed unbalance procedure in 1996 compared to 1986, when entropy coefficient decreased.Entropy coefficient, close to one, shows that space organization has balance procedure in the country levels.

Conclusion
If we draw attention to the frequency of Napierian entropy number in dwelling and population general census in 1986, 1996, 2006, we will understand that Napierian entropy coefficient of frequency of urban level has increased by three percent.This increase is for urban population in the larger states.It means population centralizes in the urban area.
Entropy coefficient has shown more number in population dispersion, but entropy coefficient frequency of Napierian has shown smaller number.It increases the number of urban points from ten cities in 1986; in 1996,23 urban points in 1385.The number of population in cities (less than a thousand populations), village and the centre of townships has increased.
Population differences of big, medium and large cities of state with these village-cities have shown high figure.And this entropy disorder is for this procedure (Table 11).
Entropy coefficient has shown balance procedure in cities level of state in three consecutively period of censuses in 1986, 1996, 2006; so we do not have centralization phenomenon and unbalance in the cities levels.
That shows population order distribution of cities in the states (Table 11).
Entropy coefficient of napievian frequency distributed in district levels has shown relativity balance in population distribution.And napievian number has increased frequently from 0/88 percent in 1986 to 0/91 percent in 2006.
It shows that population distribution has been balanced step by step in district levels of state and it has balance procedure (Table 11).
The most population number of district levels of state belongs to the east and north districts.khorramabad in the central part has special location for its crowded and high population.South and west have the least population.
At population centralization in states districts, good condition of weather in the north and east, financial centralization, mines, connective road and railway are the most important factors in those districts.
At the centre part, factors like climate, political centre services centralization, connective roads, and aerial ways are the most important factors of being crowded.
At the south and west part of the state, bad air condition is the most important factor for less population in this part of state (map number two).(1986,1996,2006)

Figure 1 .
Figure 1.Lorestan States location in the year 2006.
This model was used for the first time in Isfahan District by Mr Asghar tala Minaee in Iran.Then Mr Mojtaba Rafieean has used this model to consider Isfahan State space organization.

Table 1 .
Frequency entropy coefficient and Napierian frequency of Lorestan cities in 1986.

Table 2 .
Frequency entropy coefficient and Napierian frequency of lorestan cities in 1996.
Source: Dwelling and Population Census of Lorestan State in 1996.

Table 3 .
Frequency entropy coefficient and Nopierian of Frequency of Lorestan cities in 2006.

Table 4 .
Napierian of frequency and entropy coefficent calculation in ship of Lorestan State in 1986.
Source: Population and Dwelling Census of Lorestan State in 1986.

Table 5 .
Frequency entropy coefficcient and Napierian of frequency of Lorestan cities in 1996.

Table 6 .
Frequency entropy coefficcient and Napierian of frequency of Lorestan Cities in 2006.

Table 7 .
Napierian frequency and frequency entropy coefficient calculation in Lorestan district levels in 1986.
Source: Dwelling and population census of Lorestan State in 1986.

Table 8 .
Napierian Frequency and frequency entropy coefficient calculation in Lorestan district levels in 1996.

Table 9 .
Napierian frequency and frequency entropy coefficient calculation in Lorestan district levels in 2006.

Table 10 .
Frequency Napierian and entropy coeficient at urban levels Iran Country in .

Table 11 .
Frequency Napierian and entropy coefficient at urban levels and district and cities and town ships levels of Lorestan State and all over the Iran country in(1986, 1996  and 2006)