پویایی‌شناسی تاثیر عوامل منتخب امنیت غذایی بر امنیت ملی

Extended Abstract     
Introduction
Due to the geographical and political position of the Islamic Republic of Iran in the region and the importance of strengthening national security, it seems very necessary to identify the factors affecting it. National security is a complex and ambiguous concept that emerged after World War II and is now of great importance in all countries of the world. One of the factors affecting national security is food security, and we discuss how it impacts national security.
Methodology
Food security factors and national security criteria are identified in the researches. Given the power of the fuzzy method in explaining linguistic concepts, a fuzzy questionnaire on how each of the food security factors affects national security was designed and sent to selected experts. Using the fuzzy TOPSIS technique, which is a simplified and effective method to rank options, food security factors were classified in order of impact on national security. Factors of food health, food quality, food per capita, unit price, response speed, food freshness, food diversity, food storage, and waste are ranked first to ninth, respectively. For select the food security factors, the mean of the largest and smallest similarity index was calculated, and the factors that had a similarity index higher than this mean were selected to enter the system dynamics stage. Thus, five factors that had the most significant impact on national security - food health, food quality, food per capita, unit price, and response speed - were selected and transferred to the next step. Using the system dynamics method, which is an effective method for simulating complex systems, a system dynamics model was used to simulate the impact of selected food security factors on national security.
 Results and Discussion
Regarding the impact of food health on national security, it can be said that if food is not healthy, the health of the community is jeopardized. As a result, due to the unhealthiness of the community and the staggering costs of treatment, it threatens national security. On the other hand, increasing food health increases community health and national security, but the relationship is not exponential. That is, it cannot be said that the more food and community health increases community security, but when food health reaches its peak, its impact is asymptomatic on national security.
About the behavior of the second factor, it can be said that the food per capita of the society should be sufficiently available to the people. When people's per capita food is not enough, it has little effect on national security; if food per capita reaches a balanced level, it increases national security. If people's per capita food exceeds its balance, it will no longer have a positive effect on national security, but it will seem to have the same impact as the per capita food shortage. Since the per capita food is too balanced, the excess amount is either consumed by people, in which case it causes obesity and its underlying diseases and endangers the health of society and ultimately national security, or in the form of waste, which in this case reduces the economic power of society and threatens economic security and ultimately national security. If the country is a food importer, the increase in food per capita will increase food imports, and the amount of foreign exchange output to buy food will increase, which can ultimately harm national security.
On the impact of food quality on national security, if food is not of acceptable quality, it can increase public dissatisfaction and harm national security. Increasing the quality of food can increase general satisfaction and improve national security. But this increase appears asymptomatic because firstly, the quality of food can rise to a limited extent, and secondly, enhancing the food quality to a certain extent increases food security, and, ultimately, national security.
As to the effect of speed of response in food supply on national security, it seems that accelerating food supply will growth public satisfaction and finally increase national security, and reducing the speed of response will reduce national security. The effect of increasing the speed of response in food supply on national security is asymptomatic because, firstly, increasing the speed is somewhat possible and more than that is impossible, and more than that will not improve public satisfaction. Reducing the speed of food supply, especially in crises such as floods, earthquakes, etc., causes general dissatisfaction in society. Concerning the impact of food unit prices on national security, it can be said that increasing food unit prices augment public displeasure, and rising public discontent is a potential menace to national security. An increase in the unit price of food leads to a decrease in national security.
 Conclusion
The results of the simulation show the positive effect of health and food quality and response speed and the negative impact of unit price on national security. Also, the per capita consumption factor until it reaches equilibrium has a positive effect, and more than the balance threatens national security