مجله علوم و فناوری های پدافند نوین
سال دوم شماره 3 (پیاپی 5، پاییز 1390)

Analysis and evaluation of urban infrastructures treatment is of vital importance in natural disasters management. Among them, performance analysis of communication network, due to the extensive role in the cycle of crisis management and especially in relief stage, can have an important influence on the identification of vulnerable areas. Moreover, it results in faster relief and thus reduces the casualty. Accordingly, this paper addresses the classification of the performance of communication network in Khaksefid area (as one of the erosion texture neighborhoods with spontaneous origin) during and after earthquake through identification of vulnerability criteria of communication network in the local scale and analysis of them in that neighborhood and thus vulnerable areas are identified. The results show that in the study area, some of the roads have higher degree of vulnerability, and they will have very low efficiency at time of crisis and after. Therefore, it is necessary to use another road for relief in these cases.

One of the objectives defined in the facility location problem is dispersing facility location. On these issues, the goal is maximizing the distance between the facilities according to the constraints are available. These issues use in some cases location radio stations, schools, sales representatives and general location sensitive facilities considering passive defense principles have many applications. On the other hand the facilities operating on the principle of passive defense should be dispersed to each other, should be established in places where they can gain their mission correctly and coefficient error reduced. For considering this issue (coefficient of performance and reduce error candidate points) are suggested technique Data Envelopment Analysis with regard to criteria for choosing locations with efficient distribution model used. So in this paper a new multi-objective model for locating critical and important facility with consider of passive defense principles is presented.

Time Reversal (TiR) technique is an effective and simple method for data transmission in extremely multipath indoor UWB channels that mitigates the complexity of receiver by its own time focusing feature. Although, TiR method has the suitable performance, but it is sensitive to the non-ideal channel estimation error. In this paper at first, the bit error probability of TiR-UWB communication systems with the simple matched filter receiver and in different conditions of the channel estimation error is calculated in closed-form.Then, for improvement of the performance of the TiR-UWB system in such conditions, a pre-filter in transmitter is proposed as two stage iteration-based improvement algorithm that approaches the channel estimation error to zero in 4 steps for the TiR-UWB system including the simple matched filter receiver by means of the calculated pre-filter in the TiR-UWB system consisting on the optimal MMSE estimator. Furthermore, it is indicated analytically that the designed pre-filter depends on the existent channel estimation error covariance. The obtained equations are compared with simulations and are shown to be in good agreement.

Sevoflurane is the newest inhalation anesthetic. It is notable because of its unique characteristics. Different methods have been reported for its synthesis, the best one being a two- stage method. In the first stage of this method, 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) reacts with AlCl3 and trioxane to produce sevochlorane. In the second stage sevochlorane reacts with KF in PEG-400 solvent and sevoflurane is achieved. In this research, variables such as PEG-400, KF and reaction time have been optimized. Based on the results obtained, sevofluorane was obtained in 90% yield, under optimized reaction conditions. Also, ionic liquids were used as green solvent. It was found out that fluorination reaction of sevochlorane with KF can also be performed in ionic liquids, but, howevere, with lower yields.The maximum yield was achieved by the use of tetramethylammonium fluoride,TMAF, ionic liquid in 20% yield.

Dichlor amine resin a CB decontaminant agent was synthesized by three steps from, a commercial starting material, sulfonate cation exchange resin. Product structure of each step are characterized by FT-IR. The active chlorine (Cl+) content was checked by standard iodometry titration, active chlorine was determined to be in range of 7-11%. Investigation of decontamination efficiency of Dichlor amine with 2-chloro ethyl phenyl sulfide (simulant of sulfur mustard) at room temperature, has been done by GC instrument. Also the destractive products namely ethyl phenyl sulfone and diphenyl disulfide hydroxyl were identified by GC-MS.

Analysis of compressive loading effect resulting from underwater explosion on steel structures in the diverse range of problems from the explosive forming of plates to study of explosion effect on ships body, submarines and marine structures have been applied and studied. In this paper with aim of design and construction of underwater explosion test chamber in a practical project, the effect of charge weight on plate deformation and weight effect and charge distance on fluid maximum pressure have been studied by using ABAQUS / Explicit software and the results have been compared with available experimental results and relationships and have been accurately confirmed. By verification of conducted simulation, the initial design of cylindrical test chamber in two states without stiffener and with stiffener under the effect of underwater explosion load has been assessed. In design of chamber by using stiffener the weight of chamber is reduced that has been effective in cost reduction.

Despite the fact that using the services of outsourced data stream servers has extremely been welcomed, but still the problem of obtaining certainty about received results from these servers is one of the basic challenges in enterprises. For outsourcing these services, the user should be assured by a mechanism about the security of communication channels as well as the correct and honest function of the server, because the server may attack the integrity of the results due to economic and malicious reasons. In such attacks, some parts of results are not sent to the user or sent after being modified or delayed. In this article, we have come up with an efficient method for detecting integrity attacks in outsourced data steam systems based on auditing the results of cross computation. In this method, the main data stream has been enciphered by a key and a small part of data has been enciphered by a different key, as a dependant data stream, and sent to the server. The requested query is applied on both streams and the user judges the integrity of results by comparing the results. Our method imposes a little overhead on the user and needs no change in the structure of the server. The Probabilistic modeling of the method shows that this method has a high efficiency and the results of the exprimental analysis confirm this very well.

In different fields, including military industries, for whether military forces’ or military armament, Camouflage is of high importance. Which camouflage pattern, therefore, in what size, with which color composition is more suitable for soldier’s camouflage, in a specific environment. The performance of camouflage patterns are usually estimated based on the time needed for recognizing the concealed object. This effort is seeking to prepare a computer software to answer such questions. Having images of camouflage Environment, Pattern & Object, this software designs a test; The result of each test is the “mean recognition time” among the background image. The prepared software has advanced features such as zoom background image, change size, angle, color and camouflage schemes, blur the edges of the object, the size of an object to be camouflaged, and so on. The results were analysed several times and through different ways, and are compatible with the proved principles of Camouflage issue.