فصلنامه پدافند غیرعامل
سال چهارم شماره 3 (پیاپی 15، پاییز 1392)

This article intends to identify and provide passive defense courses of action for power distribution systems in order to reduce vulnerability level when struck and threatened by insurgent and threatening groups. In this regard, a model of critical flow of the distribution system is firstly presented. Then by determining the vulnerable points of the power distribution system of Iran and by considering various kinds of threat factors, threats are verified. Later, mitigation methods of vulnerability level before, while and after being struck, will be examined and analyzed.

Due to the need of some organizations, especially military organizations to complex systems, modeling and simulation methods are used to evaluate and analyze the performance of these systems. One of the tools used for this purpose is the artificial intelligence algorithm. In this regard, the materials and goods flow, human resources, information and so on, can be modeled. By modeling and adjusting various scenarios, the system can be analyzed and efforts are made for potential improvements. Some of these algorithms are: genetic, neural networks, ant colony, simulated annealing and forbidden or taboo search. These algorithms will be used for such complex and non-deterministic systems as in aerial concealment, safe covert systems, considering other passive defense approaches. Therefore; this approach has several design solutions for optimizing the diagnostic quality and better strategies to understand and improve the performance, making decisions about the system under time constraint issues, acceptable. Based on the categories and their different types, these algorithms, have their own performance, functionality and features and application field and will help us in solving optimization problems. This paper intends to study and introduce artificial intelligence algorithms to solve optimization problems based on the resources and research conducted in this field. Therefore, taking the advantages, disadvantages, applications, processing time, data volumes and application field of each of them into considerations, experts in the field can select and utilize the best and most optimum algorithm to solve the complex and inconsistent problems.

In the information hiding systems, three main elements of capacity, security and resistance are involved. Security and emplacement capacity have a special position in steganography and the steganography methods emphasize the reduction of changes caused by emplacement. But one of the very important issues in passive defense is the appropriate application of the existing memory space for steganography during crisis. This paper attempts to present a dynamic method to implement image steganography by considering minimum factors in the image properties for critical conditions. The consumed memory space and the similarity of image are two parameters that are dealt with in this paper. In this paper, at first, a compressed image of the main image is obtained using the Takin Value Analysis Method and then the steganography is performed. In this method, steganography in the compressed image supplement is done and later, will be accumulated with the compressed image itself and the ultimate image will be obtained which resembles the main image and this similarity value depends on the value of the special parameter in the computational process called K(special value of matrix). The lower the value of K, the lower the similarity to the main image but a higher memory space will be available for steganography.

In regard to the increase in risk of war and aggression in today's world specially Iran's specific position in current time, using principles of passive defense in buildings is inevitable. On the otherhand, every day we are facing problems in the world and our country Iran due to lack of energy. In this article attempts have been made to consider these two important factors, which our country is facing by studying the issue of green view topic. In this regard, walls and green views, are not only important to conserve energy and reduce negative effects of buildings on the environment but they also play a significant role from the perspectives of passive defense and such principles as camouflage, concealment and deception. The information collected in this article is taken from library research methods and valid sources on the Internet. In this regard, at first the principles of passive defense and the buildings that have beendesigned according to these principles, have been studied, then the effects of blast effects and e waves on surroundings were investigated and the results have been collected and analyzed and the assumption of using green wall as a solution for the purpose of reducing energy has been provided and examined. According to the achieved information, green view, in addition to its many benefits in energy debate, has some benefits in the field of passive defense too, such as integration of spaces, shaping buildings, absorbing infrared and, electrical waves and control of blast wave, as well.

Fiber reinforced concrete is widely used for improving the dynamic properties of concrete structures against blast effects, shock and penetration in passive defense, military and hardening projects. Adding fibers to concrete increases toughness, ductility, tensile and flexural strength of concrete especially against impact and dynamic loads and control the crack propagation and spalling of the concrete. Research conducted on steel fiber reinforced concrete has been done mostly using imported fiber. In this study, domestic steel fibers were tested to investigate their effect on mechanical properties of concrete. Test results showed that adding this type of fiber considerably improves the compressive, flexural and tensile strength of concrete. Consequently, it is expected that adding this type of steel fibers in concrete will dramatically increase its strength against very heavy loads such as impact and explosion.

Cities are one of the most important targets in wars. Hostile countries intend to disrupt centers of gravity of these countries in order to neutralize their defensive systems. In cities, roads and passages are the most important war targets in future confrontations. Without roads and passages, a city’s transportation facilities will be disrupted and will cause the defensive systems to be inactivated. Therefore; to defend cities, protecting passage networks is a necessary issue. The first step to defend city roads and passages is to determine the possible vulnerable points of these roads and passages and furthermore; necessary measures must be taken in this regard. This essay attempts to investigate the vulnerability of one of the most important city roads in north Tehran – Iran, The Martyr Sadr Elevated Expressway. In order to determine the vulnerability rate of this Elevated Expressway, at first, some parameters influencing the vulnerability of this Elevated Expressway were identified and weighted and then they were assessed in the format of information layers in ESRI-ArcGIS desktop package, and the vulnerability maps of the expressway were created. At the end, one of the most identified vulnerable points was reviewed and the influencing parameters of this point was expressed.

Organize the land is known as the proper organization of living space in the form of land use policies and defense necessities. One of the implications of land use, is the proper organization of space for development. Acts of defense perspectives for locating vital installations like refineries is essential. So far,in the design of refineries safety measures is observed, And it seems that the considerations of defensive positioning is not much focused. Observaning and considering measures such as geographical location, type and level of threat, source of threat and defensive schemes tailored to the threat, are the most important parameters. Because Border provinces have particular circumstances and political differences, the spatial location within the facility must be executed with special considerations. Bandar Abbas refinery is in the vicinity of potential threat of transregional forces in the Persian Gulf and has a special status. In this paper we analyze the method in the context of software systems, GIS and field observations, Look for the answer in locating of the refinery of Bandar Abbas that which defensive considerations are observed? Initially a discussion about considerations of defensive positioning, and then explaining the importance of its refinery in Bandar Abbas in Hormozgan Province and the Persian Gulf region is evaluated, Resulting in noncompliance with a series of defensive considerations in site selection of this critical this project.