فصلنامه پدافند غیرعامل
سال چهارم شماره 2 (پیاپی 14، تابستان 1392)

This essay is intended to investigate and test the effects of different kinds of smoke on radar wave portion of the electromagnetic spectrum. In regards to the use of electromagnetic waves in the world's current sensors and detectors, the necessity of passive defense and in other words, camouflage against these equipments, is of utmost importance. The use of smoke is one of these ways. Therefore, to perform camouflage, the simulation of a laboratory environment is required which can approximate the smoke camouflage against radar waves as much to the field and operational conditions, as possible. In this essay, a review of the camouflage strength of several material against the radar X- band has been implemented and eventually, taking their reflective coefficient rate into consideration, the carbon fiber as the material which could cause a reduction of 6db in the reflexive coefficient and hence, can be used as a camouflaging material against radar waves.

Every electrical power grid as an interconnected system has one or more bottleneck components. If in any case, these components are attacked and lose their systematical functions, the grid will partly or completely collapse. In case of electrical blackout, all of the dependent infrastructures will fall in an increasing crisis in their necessary activities; because since the beginning of blackout, selfretaining ability of subsystems such as economic, social and political will decrease more and more. In this paper, the NATO war against former Yugoslavia (1999) and the USA and its allied nations war against Iraq (2003) were studied primarily focusing on objectives, strategies and the attacker's actions against power grids. Based on these studies, and also considering the existing condition of power grid in our country's structure from technical perspectives and its sustainability management, measures have been taken to extract strategic topics in the power grid sustainability system based on the passive defense implications. This is done according to comparative method through comparison between equivalent components of deterrence strategy and sustainability management principles. The said topics are based on the necessity of elements importance through ranking to recognize system bottlenecks to withstand enemy first attack and restoration plan as instruction to do the second passive response to him.

Tunnels are one of the access elements to underground structures playing a vital role in passive defense. In regard to the high cost of constructing tunnels, many methods have been presented to improve and make such projects more cost effective. One of the common methods in our country to construct tunnels is the ditching and firing. In tunnel construction using ditching and firing, the explosive features are determined, taking the stone material of the tunnel site into consideration. The number and diameter of blast holes, type and the amount of explosive material to be used and the explosion pattern, as well, are among the items to be determined. One way to reduce the costs is to use the appropriate type and amount of the explosive material which is in turn, dependent on knowing the specifications of the explosive material and tunnel site stone. The explosive material is especially important due to properties such as density, blast velocity, impedance, energy in mass unit and pressure. Therefore, the type and explosive material for every stone should be exactly identified. Predicting the destruction intensity is dependent on long experience, repeating several explosions and observing the results. In general, after several explosions and observing the results,the optimum amount of explosive material will be determined with trial and error. The explosion simulation before performing the main operation can be one of the appropriate methods to reduce time, costs and predicting better explosion-induced results. In this essay, the equations governing blast wave propagation are solved using limited numerical elements and the behavioral model of RHT has been used as the criteria of separation and submission of stone material. The results of this research indicate that in order to choose reliable explosive material to destroy stones, the most effective variable is the amount of energy on the mass unit of that explosive material. The analytical results of the project sensitivity can be used to reduce the costs of underground passive defense projects.

A country's defensive system is divided into two passive and active defense and the passive defense is described as those unarmed measures which will contribute to the vulnerability reduction of manpower, buildings, facilities, equipments, assets and the country's vital routes against hostile and destructive operations of a potential enemy. One of the passive defense policies in every country in general, and Iran in particular, is constructing public shelters to safeguard citizens and reduce damages in human domain. But what appears to be important in compliance with the said policy is the site position or the desired limits to construct public shelters. This essay which has been prepared for site location of public shelters with passive defense approach in the City of Tehran, Region 16, while investigating and studying the subject matter literature in the fields of passive defense, shelter and site location, presents eleven indicators of site location of public shelters in the format of four general criteria. And in the next step, it deals with the coefficients of importance indicators and criteria using network process analysis technique (ANP), and in the end, through overlapping information layers (Overlay) and executing these coefficients in the Arc GIS software domain, identifies the best reference locations compatible with the objective. The research results indicate that, of the introduced indicators, three indicators such as indicators of proximity to applications suitable for support role, deployment in a proper distance of the enemy's targeted functions and proximity to population attraction centers, contain the highest importance coefficient in the process of the selection of public shelter deployment from the expert's views. In the meantime, based on the research findings, there is a meaningful relationship between the deployment locations of public shelters and the local, regional and area structures.

Protecting active operational forces in rescue operations in sensitive situations due to natural disasters or enemy attacks is considered as a basic strategy in national macro management strategy. Therefore, having useful information in this regard is of utmost importance and has a significant position to increase the defensive power of every country. In this study, data from specific sensors installed on clothes and carry-on equipment of an operational force are saved after sampling and initial processing. The received information can be classified in three categories. This information in appropriate data packages (with encryption to protect data security) are transmitted to the control center of system using cellular telecommunications network infrastructure (using GPRS service). These data packages after being filtered and displayed in monitoring software, are stored in main system database. The first group of received information contains vital signs such as heart rate signals, body temperature, blood pressure and blood sugar. The second group contains environmental condition information such as temperature, humidity, amount of oxygen and CO2, air pressure and lighting of environment. The third group contains spatial-time information such as latitude and longitude, the precise time, speed and the tempo in case of the force mobility. By designing and implementing prototype of this system, using the said information, the location and environmental conditions of the forces were informed and the health and performance of the forces were successfully monitored. The results can be used in management planning and performance measurement of rescue teams in training, maneuvers and real rescue operations.

In countering an enemy's military, intelligence and security provocations, applying passive defense tools is inevitable. In today's world, applying passive defense to counter these issues in regard to less cost and low vulnerability and the ease of its implementation is the most essential tool and something that has always been noticed. Recently, regarding the high scientific, technical and military advances, these techniques have emerged in a modern manner. One of the most important systems in passive defense is the authenticity or certainty in detecting the truthfulness of a person's words through brain signal processing. In this essay, with the intent of presenting a capable method to detect the guilty person in the lie detectors, a method based on recognition parameter called P300 has been designed and reviewed. For this reason and based on the Odd-ball Pattern(reconstruction of hidden figure) a test has been designed and the brain signals of 18 people have been recorded. And finally Guilty and Innocent persons were classified through Bootstrapped Correlation Difference (BCD) method. The validated results show the promise of the proposed approach by the accuracy of 94.5%.

Web services play an important role in the development of service-oriented architecture and distributed architectures. Web services allow the reuse of software code and thus reduce the cost of programming and communication, they have received much attention in recent years, due to the use of the Internet as a medium of data transmission and autonomy of hardware and software platforms. On the other hand, Web services have specific security challenges. This is especially important when the organizations are dependent on the service in the form of Web services. In this case, with the weakness of the current security systems to protect Web services, these organizations are defenseless against all types of known and unknown threats that threaten Web services.Nowadays, intrusion detection systems, are well-known to complete the levels defense in cyberspace. The main purpose of this article is to conduct research on intrusion detection techniques and architectures of Web services to support passive defense issues in organizations that make use of Web services.The comparison between the architectures of intrusion detection, to achieve a high level of understanding of intrusion detection techniques in the web services, will help to improve current intrusion detection systems in the level of Web service, or to make specific intrusion detection systems for these services along with other security tools.