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Multidisciplinary Design and Optimization of Multistage Ground-launched Boost Phase Interceptor Using Hybrid Search Algorithm

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Chinese Journal of Aeronautics 2010年第2期23卷 170-178页

作者： qasim zeeshan Khurram Nisar Ali Kamran Amer Rafique School of Astronautics Beijing University of Aeronautics and Astronautics

This article proposes a multidisciplinary design and optimization （MDO） strategy for the conceptual design of a multistage ground-based interceptor （GBI） using hybrid optimization algorithm, which associates genetic algorithm （GA） as a global optimizer with sequential quadratic programming （SQP） as a local optimizer. The interceptor is comprised of a three-stage solid propulsion system for an exoatmospheric boost phase intercept （BPI）. The interceptor＇s duty is to deliver a kinetic kill vehicle （KKV） to the optimal position in space to accomplish the mission of intercept. The modules for propulsion, aerodynamics, mass properties and flight dynamics are integrated to produce a high fidelity model of the entire vehicle. The propulsion module com- prises of solid rocket motor （SRM） grain design, nozzle geometry design and performance prediction analysis. Internal ballistics and performance prediction parameters are calculated by using lumped parameter method. The design objective is to minimize the gross lift off mass （GLOM） of the interceptor under the mission constraints and performance objectives. The proposed design and optimization methodology provide designers with an efficient and powerful approach in computation during designing interceptor systems.

关键词： boost phase genetic algorithm grain design interceptor optimization solid rocket motor

Hyper Heuristic Approach for Design and Optimization of Satellite Launch Vehicle

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Chinese Journal of Aeronautics 2011年第2期24卷 150-163页

作者： Amer Farhan RAFIQUE HE Linshu Ali KAMRAN qasim zeeshan Department of Spacecraft Technology School of Astronautics Beihang University Beijing 100191 China Department of Space Propulsion School of Astronautics Beihang University Beijing 100191 China

Satellite launch vehicle lies at the cross-road of multiple challenging technologies and its design and optimization present a typical example of multidisciplinary design and optimization（MDO） *** complexity of problem demands highly effi-cient and effective algorithm that can optimize the *** heuristic approach（HHA） based on meta-heuristics is applied to the optimization of air launched satellite launch vehicle（ASLV）.A non-learning random function（NLRF） is proposed to con-trol low-level meta-heuristics（LLMHs） that increases certainty of global solution,an essential ingredient required in product conceptual design phase of aerospace *** empirical study is performed to evaluate the performance advan-tages of proposed approach over popular non-gradient based optimization *** of ASLV encompasses aerodynamics,propulsion,structure,stages layout,mass distribution,and trajectory modules connected by multidisciplinary feasible design *** approach formulates explicit system-level goals and then forwards the design optimization process entirely over to *** distinctive approach for launch vehicle system design relieves engineers from tedious,iterative task and en-ables them to improve their component level *** is an impetus on vehicle performance and cost,and so it is considered as the core of vehicle design ***,gross launch mass is to be minimized in HHA.

关键词： multidisciplinary design optimization satellite launch vehicle heuristic optimization methods hyper heuristic air launched vehicles

Finocyl Grain Design and Optimization Using Sequential Quadratic Programming

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Computer Aided Drafting,Design and Manufacturing 2008年第1期18卷 1-11页

作者： KHURRAM Nisar qasim zeeshan School of Astronautics Beijing University of Aeronautics and Astronautics

Design technique of 3D Finocyl grain configuration for Solid Rocket Motors, including its performance prediction and optimization is discussed. In doing so, the design objectives and constraints are set, geometric parameters of Finocyl grain are identified, and performance prediction parameters are calculated, thereafter the preliminary design is completed and optimal design is reached. For every grain design, it is necessary that the minimum possible mass of propellant is used to produce the required thrust within a certain limit of burning time. By using this technique of design and optimization, the vital parameter of propellant mass is optimized to its minimum value, yet vital parameter of thrust is attained in the required burning time with the fixed length and diameter of motor. Especially a geometrical model of grain configuration is developed by using various combinations of ellipsoid, cone, cylinder, sphere, torus and inclined plane. With the diameter of the motor fixed, the Finocyl Grain geometry totally depends on sixteen independent variables. Each of these variables has a bearing on explicit characteristic of Finocyl grain design and optimization. Changing the value of each of these variables brings significant effects on the performance. Due to such attributes of Finocyl grain configuration, compromises will result. Overall optimal design is ensured through assigning and analyzing a suitable range of geometric parameters satisfying the requirements of minimum mass of propellant and ensuring sound values for internal ballistic parameters while remaining within the design constraints of thrust, burning time, length and diameter of chamber case.

关键词： solid rocket motor 3D finocyl grain geometry internal ballistics optimization

Conceptual Design Architecture Modeling and Simulation for Boost Phase Ballistic Missile Defense

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Computer Aided Drafting,Design and Manufacturing 2008年第1期18卷 47-65页

作者： qasim zeeshan MOATASEM Momtaz School of Astronautics Beijing University of Aeronautics and Astronautics

The design review, simulation and validation of a Conceptual Design Architecture (CDA) for Ballistic Missile Defense (BMD) are presented. An intercept system that contains a Ground Based Interceptor (GBI) and its guidance sensors (both radar and infrared) are simulated. 3D model using MATLAB is developed for a multistage target with ascent phase acceleration profile that depends on total mass, propellant mass and the specific impulse in the gravity field. The radar cross section (RCS) and infrared radiation (IR) of the target structure is estimated as a function of the flight profile. The Kill Vehicle (KV) design is examined as a function of the KV mass, acceleration capability, aimpoint offset and impact energy to destroy the target. The aim of the CDA is to: detect the launch of a threat ballistic missile, determine whether the detected object is a threat,define the characteristics of the threat ballistic missile, develop a firing solution to negate the threat ballistic missile, engage the threat ballistic missile, and assess the effectiveness for ballistic missile intercept. The architecture is modeled in Matlab.

关键词： ballistic missile infrared radiation interceptor missile kill vehicle, radar cross section solid propulsion trajectory

GPS Navigation Using Adaptive Kalman Filter for Maneuvering Vehicle

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Computer Aided Drafting,Design and Manufacturing 2008年第1期18卷 83-87页

作者： MOATASEM Momtaz qasim zeeshan School of Astronautics Beijing University of Aeronautics and Astronautics

Several filter techniques were available for the GPS position estimation problem of maneuvering vehicle ranging from using different process noises to Interactive Multiple Model (IMM). The limitation of using standard Kalman filters is *** performance of proposed adaptive filter is compared with that of the standard ones,two types of dynamic modeling of the maneuvering vehicle are *** simulation is based on the almanac data of the GPS satellites to compute its feasibility during the simulation time and position on shape 8 track with continuous vehicle maneuvering. The goal is to obtain computationally efficient filter with reasonable accuracy for vehicle in maneuvering situation. The filter proposed is an alternative to the filter proposed in Ref. [1] with low computational burden.

关键词： GPS maneuvering fling Kalman filter adaptive Kalman filter

Topology Optimization for Manufacturable Configuration Design of Aircraft Tail Rib

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Computer Aided Drafting,Design and Manufacturing 2009年第1期19卷 94-101页

作者： WAQAS Saleem qasim zeeshan School of Mechanical Engineering and Automation

A methodology is implemented to find the optimum reduced weight configuration design of an operating structure of a civil aircraft vertical tail fin. FE （finite element） based topology optimization is executed to find the optimum material distribution of initial design space of rib by maximizing the stiffness. Loads pertinent to the operating and ground conditions are estimated and applied, considering the orientation of structural assembly members and built-in supports offered in the main structure. Manufacturing constraints are incorporated into the optimization loop to generate pragmatic and manufacturable design configuration. The topologically optimized configuration is then converted to CAD viable design through data reduction and smoothing by converting to ISO-surfaces. A methodology is also devised to modify the topological optimized voids and material layout precisely with splines and fillets to construct manufacturable features and avoid stress concentrations. The resulting novel design proposal is then analyzed and validated against stipulated loads, constraints and other design needs. Results validate the new design proposal as more reliable, having reduced weight and enhanced structural performance.

关键词： CAD topology optimization TOSCA tail fin

Multidisciplinary Design and Optimization of Satellite Launch Vehicle Using Latin Hypercube Design of Experiments

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Computer Aided Drafting,Design and Manufacturing 2009年第1期19卷 1-7页

作者： AMER Farhan Rafique qasim zeeshan School of Astronautics Beijing University of Aeronautics and Astronautics

The design of new Satellite Launch Vehicle （SLV） is of interest, especially when a combination of Solid and Liquid Propulsion is included. Proposed is a conceptual design and optimization technique for multistage Low Earth Orbit （LEO） bound SLV comprising of solid and liquid stages with the use of Genetic Algorithm （GA） as global optimizer. Convergence of GA is improved by introducing initial population based on the Design of Experiments （DOE） Technique. Latin Hypercube Sampling （LHS）-DOE is used for its good space filling properties. LHS is a stratified random procedure that provides an efficient way of sampling variables from their multivariate distributions. In SLV design minimum Gross Lift offWeight （GLOW） concept is traditionally being sought. Since the development costs tend to vary as a function of GLOW, this minimum GLOW is considered as a minimum development cost concept. The design approach is meaningful to initial design sizing purpose for its computational efficiency gives a quick insight into the vehicle performance prior to detailed design.

关键词： multidisciplinary design and optimization satellite launch vehicle solid propulsion liquid propulsion latin hypercube sampling design of experiments

Stealth Considerations for Aerodynamic Configurations Design of Missiles

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Computer Aided Drafting,Design and Manufacturing 2009年第1期19卷 8-16页

作者： qasim zeeshan ALI Kamran AMER F Rafique KHURRAM Nisar School of Astronautics Beijing University of Aeronautics and Astronautics

The aerodynamic design of a strategic weapon is of interest, especially when the radar signatures are included in the conceptual design phase. The basics of stealth configurations and stealth mechanisms for missiles are reviewed. The Radar Cross Sections （RCS） of some generic missiles are predicted and compared to analyze the trade-offs involved between low RCS and aerodynamic performance. The consideration of RCS prediction in the conceptual design phase gives a quick insight into the stealth performance prior to detailed design.

关键词： aerodynamic configuration missiles radar cross section radar absorbent material stealth

Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 123-153页

作者： Muhammad qasim Khan Fazal Malik Fahad Alturise Noor Rahman Department of Computer Science Iqra National UniversityPeshawar25000Pakistan Department of Cybersecurity College of ComputerQassim UniversityBuraydah52555Saudi Arabia Department of Computer Science and Engineering Al-Fayha CollegeAl Jubayl31961Saudi Arabia

Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband ***,they consume important and scarce network resources such as bandwidth and processing *** have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial *** paper draws its motivation from such real network disaster incidents attributed to signaling *** this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and *** provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding *** important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a *** paper presents an update and an extension of our earlier conference *** our knowledge,no similar survey study exists on the subject.

关键词： Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication