Research Paper
space sciences and exploration
Iman Shafieenejad
Articles in Press, Accepted Manuscript, Available Online from 25 July 2023
Abstract
The aim of this research is to optimize the trajectory of a low-trust spacecraft carrying biological cargo. Reducing the radiation stresses of the Van Allen belt is the optimal criterion of the optimal control problem of the orbital transfer from the low orbits to the high orbits. Since the minimum radiation ...
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The aim of this research is to optimize the trajectory of a low-trust spacecraft carrying biological cargo. Reducing the radiation stresses of the Van Allen belt is the optimal criterion of the optimal control problem of the orbital transfer from the low orbits to the high orbits. Since the minimum radiation stress criterion introduced in this article is not among the conventional optimality criteria, solving the above optimal control problem will be complicated and the honey bee optimization method has been used. The optimization of the path in this article is done by rewriting the motion equations based on the control variable and solving the new motion equations with the help of bee optimization. The main advantage of the method used in this problem is the use of optimal control theory and population-based optimization methods with a global approach. In the presented new method, the optimal control problem is simplified by redefining the differential equation system, and the results show the accuracy and ease of solution. Results of the optimal criterion of the minimum time and the minimum radiation stresses presented in this article, the criterion of the minimum radiation causes an increase of 8.89% in the transfer time.
Research Paper
communications
Jaafar Bazrafshan; Fatemeh Sadeghikia; Ali Karami Horestani; Mohamed Himdi
Articles in Press, Accepted Manuscript, Available Online from 25 September 2023
Abstract
This paper presents a novel approach for designing a reconfigurable and steerable antenna utilizing plasma dielectric slabs along the aperture of a pyramidal horn antenna. The antenna offers electronic control over both the radiation gain and the direction of the main beam. The proposed configuration ...
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This paper presents a novel approach for designing a reconfigurable and steerable antenna utilizing plasma dielectric slabs along the aperture of a pyramidal horn antenna. The antenna offers electronic control over both the radiation gain and the direction of the main beam. The proposed configuration consists of four plasma slabs aligned perpendicular to the horn aperture along the horn axis, complemented by four diagonally connected plasma slabs. Each plasma slab can be independently switched ON or OFF, enabling dynamic adjustment of the radiation gain and steering of the main beam. Numerical investigations demonstrate that toggling the plasma slabs or controlling the plasma frequency of these slabs allows for fine-grained control over the radiation gain and beam steering of the pyramidal horn antenna. The selection of appropriate dimensions and angles for the plasma slabs plays a crucial role in achieving the desired beam steering angle and radiation gain control. To validate the concept, the proposed antenna configuration is designed and numerically simulated at a frequency of 10 GHz. The results indicate that the radiation gain of the antenna can be significantly enhanced, reaching up to 6.5 dBi. Additionally, the main beam direction can be steered within a range of ±12 degrees.
Research Paper
Space subsystems design: (navigation, control, structure and…)
hamid reza ali mohamadi; Hassan Naseh
Articles in Press, Accepted Manuscript, Available Online from 25 September 2023
Abstract
Achieving to new technologies with high reliability, along with reducing the cost and time of the design cycle, is one of the most important challenges in complex systems. In this paper, reliability based design of a space system is discussed in the conceptual design phase. Normally, there are eight ...
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Achieving to new technologies with high reliability, along with reducing the cost and time of the design cycle, is one of the most important challenges in complex systems. In this paper, reliability based design of a space system is discussed in the conceptual design phase. Normally, there are eight steps in the design for reliability. The first step, planning, and the next seven steps that applied for the liquid propellant engine with electro-pump technology included: determination of failure modes; reliability modeling; reliability allocation; propagation of uncertainty; Implementation of the chosen method in reliability analysis; reliability prediction and reliability evaluation. Therefore, in this research has been performed to achieved method and implementation steps of reliability design in the conceptual design phase of a space system.
Research Paper
space sciences and exploration
Ebrahim Amiri; Masoome Khani Chamani; Mahdi Jafari-Nodoshan; Sajjad Ghazanfarinia; Masoud Khoshsima
Articles in Press, Accepted Manuscript, Available Online from 16 December 2023
Abstract
The economic model generally expresses the mechanisms used to earn money from a business, and if it doesnot generate income, its failure will be certain. Therefore, the decision to carry out a mission isnot only based on technical specifications, and besides that, economic profitability is another part ...
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The economic model generally expresses the mechanisms used to earn money from a business, and if it doesnot generate income, its failure will be certain. Therefore, the decision to carry out a mission isnot only based on technical specifications, and besides that, economic profitability is another part of decision-making and will be one of the main factors for commercial investments. Space projects, as wellas moon-mining projects, are no exception to this rule and require an all-round approach to compare financial and technical feasibility. Analyzing the economic feasibility of any project can be summed up in the evaluation of its economic model. In this regard, a model is needed to compare, rank and determine the available options, which is economically justified. In this paper, the economic evaluation of moon-mining based on the materials available on the moon and sending them to the earth is discussed. Materials with economic priority are categorized and selected in a fuzzy evaluation and using an economic model suitable for space mining, an economic evaluation for the business of selling materials on the Earth is carried out and according to economic efficiency, the type of material and also the high-level specifications of the project has been extracted.
Research Paper
cellular-molecular biology
Zahra Hajebrahimi
Articles in Press, Accepted Manuscript, Available Online from 30 December 2023
Abstract
Simulated microgravity can change tumor cell adhesion, proliferation, invasion, and metastasis. E-cadherin molecule is a cell-to-cell adhesion regulatory molecule whose expression is reduced in most types of cancer cells. In the present study, the expression of the E-cadherin gene in the MCF-7 breast ...
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Simulated microgravity can change tumor cell adhesion, proliferation, invasion, and metastasis. E-cadherin molecule is a cell-to-cell adhesion regulatory molecule whose expression is reduced in most types of cancer cells. In the present study, the expression of the E-cadherin gene in the MCF-7 breast cancer cell line was studied under simulated microgravity conditions using Clinostat for one and three days using real-time PCR technique and GAPDH as reference gene . Also, the effect of microgravity on cells was evaluated by the MTT test. MTT data showed that microgravity for one and three days has no significant effects on cell proliferation and metabolic activity. Also, microgravity for one day led to a doubling of E-cadherin gene expression. The continuation of microgravity for three days led to a further increase. As a result, microgravity can lead to the reduction of the cancerous phenotype in breast cancer. Therefore, studying cancer cells in a microgravity environment can help us understand the mechanisms that lead to cancer and its progression. Also, these studies can lead to the development of new treatment methods for cancer treatment.
Research Paper
Space systems design (spacecraft, satellites, space stations and their equipment)
Sajjad Gharezi; Mohammad Mehdi Doustdar
Articles in Press, Accepted Manuscript, Available Online from 17 January 2024
Abstract
In this research, the design of a can combustion chamber for a ramjet engine, the performance of this chamber and the role of flameholder have been studied. For this purpose, after talking about ramjet engine types, some general information about the combustion chamber has been explained. Then the process ...
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In this research, the design of a can combustion chamber for a ramjet engine, the performance of this chamber and the role of flameholder have been studied. For this purpose, after talking about ramjet engine types, some general information about the combustion chamber has been explained. Then the process of chamber designing and determining its geometry has been discussed. The dimensions of the chamber were determined by using input conditions extracted from GasTurb software as well as applying a calculation code, and the geometry of the chamber have been determined by applying calculation codes. By evaluating the obtained geometry and ensuring the accuracy of the design, simulation of combustion with non-premixed liquid phase was carried out using Fluent software. While presenting the results, the effects of size, distance and number of flameholder have been investigated. It is shown that the use of flameholder in ramjet engines is essential but the use of large flameholder is not recommended.
Review Paper
communications
Pedram Hajipour; Hossein Eftekhari; Ali Kheirdoost; Hassan Yeganeh
Articles in Press, Accepted Manuscript, Available Online from 03 March 2024
Abstract
Satellite constellations include a set of similar satellites that are distributed in a specific orbital pattern to accomplish a common mission. Satellite constellations are commonly used to accomplish missions such as global telecommunications, global positioning, and remote sensing. In this article, ...
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Satellite constellations include a set of similar satellites that are distributed in a specific orbital pattern to accomplish a common mission. Satellite constellations are commonly used to accomplish missions such as global telecommunications, global positioning, and remote sensing. In this article, by using scientometric approach, the structure and scientific maps of the field of "satellite constellations" in the world, as well as two leading countries, including the United States and China, have been analyzed based on research documents published in this field. In addition, a comparison has been made between these two countries with the world. The research community includes all scientific documents in the field of "satellite constellations" that have been indexed in the "Scopus" database between 1969 and 2023 AD. Also, in this article, knowledge maps (thematic subfields) and international cooperation maps of countries have been drawn using Bibexcel and VOSViewer software.
Research Paper
Space subsystems design: (navigation, control, structure and…)
Milad َAzimi
Articles in Press, Accepted Manuscript, Available Online from 07 April 2022
Abstract
This paper deals with semi-analytical modeling and stability analysis of a coupled slosh-tank dynamics as a multibody system using the Homotopy Perturbation Method (HPM). The sloshing motion of the liquid inside the tank is considered as the equivalent pendulum model. The nonlinear equations of the motion ...
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This paper deals with semi-analytical modeling and stability analysis of a coupled slosh-tank dynamics as a multibody system using the Homotopy Perturbation Method (HPM). The sloshing motion of the liquid inside the tank is considered as the equivalent pendulum model. The nonlinear equations of the motion under lateral and longitudinal excitations (compressive oscillations) are derived using the Lagrangian approach. In this model, the effects of essential parameters such as viscous damping, amplitude, and frequency of the excitation are studied for two typical points inside and outside the stability regions. It has been shown that viscous damping, compared to other principle parameters, brings the points located in the unstable region closer to the stable region. The simulations in terms of stability diagrams, phase portraits, and time histories of sloshing amplitude are achieved using HPM and compared to the numerical Runge-Kutta method to follow the stability phenomena and highlight the analytical approach's validity.
Research Paper
Space New Technologies
Reza Amjadifard; Ehsan Mousivand; Farhad Bagheroskuee; Shahab Karbasian; Ehsan Kosari
Articles in Press, Accepted Manuscript, Available Online from 09 April 2024
Abstract
The prioritization and verification of space emerging technologies is a multi-step, iterative process that needs to collective intelligence (the participation of all stakeholders), as well as the use of analytical methods to identify requirements. This process begins with identifying specialists who ...
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The prioritization and verification of space emerging technologies is a multi-step, iterative process that needs to collective intelligence (the participation of all stakeholders), as well as the use of analytical methods to identify requirements. This process begins with identifying specialists who have enough knowledge and experience regarding to each technology, and followed by extracting and evaluating the necessary data, prioritizing technology options, identifying challenging technologies and the essential acquisition strategy, and finally prioritizing them. In this article, we implemented a method to identify and prioritize some space technologies which could be used in the electrical power subsystem (EPS) of a satellite. Based on the results, it would be possible to choose the best method to access the required technology; national development or benefiting of available technology in the market. To evaluate the suggested method, the power subsystem components are divided into three categories: electrical power generation sources, energy storage sources, and power electronic circuits. Applying the proposed method shows that the selected technologies are those is recently used in space. This method can also be applied to other subsystems.
Research Paper
Space subsystems design: (navigation, control, structure and…)
Moslem Karim Abadeh; Morteza Tayefi
Articles in Press, Accepted Manuscript, Available Online from 09 April 2024
Abstract
In this study, the control of a space capsule during the re-entry phase is examined. Re-entry is one of the most important phases of a spacecraft's mission because when the spacecraft enters the Earth's atmosphere, aerodynamic forces and moments will disturb the angles of attack and side slip. These ...
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In this study, the control of a space capsule during the re-entry phase is examined. Re-entry is one of the most important phases of a spacecraft's mission because when the spacecraft enters the Earth's atmosphere, aerodynamic forces and moments will disturb the angles of attack and side slip. These disturb angles, if not controlled, can cause serious injuries to the spacecraft and its passengers. To eliminate the disturbances, moving mass controllers have been used as an operator. Moving mass controllers (MMC) control the flying device by creating an internal force. The main advantage of moving mass controllers compared to other operators such as aerodynamic surfaces and thrust jets is the non-production of turbulent aerodynamic force (which can disrupt the controller's performance) due to the creation of internal force. Another important factor is the mechanism of moving mass controllers. In this research, in addition to the cross mechanism, which is a more common mechanism, the radial mechanism has also been examined. A non-linear controller is needed in order to use the radial mechanism, and in this research, a non-linear proportional-integral-derivative controller is suggested.
Research Paper
Space systems design (spacecraft, satellites, space stations and their equipment)
Amirhossain Adami; zahra pourJabari; Mohammad azhdari; Ali Saadat dar; Hanieh Eshaghnia; Kazem gholipour; seyedmohammad mirmohammadi; Alireza Ahangarani Farahani
Articles in Press, Accepted Manuscript, Available Online from 21 April 2024
Abstract
In this research, the structure of the probes sent to other planets is first investigated and the common structures are introduced. In the following, the system design process of the Armita probe, which was prepared for the first national competition of the probe robot (Iran Space Research Institute), ...
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In this research, the structure of the probes sent to other planets is first investigated and the common structures are introduced. In the following, the system design process of the Armita probe, which was prepared for the first national competition of the probe robot (Iran Space Research Institute), will be discussed. Armita team has won the first place in the first phase of the competition in 1401. The probe design process is based on the ECSS standard and is presented briefly, which includes the compilation and extraction of the requirements document, function-performance tree, product tree and finally the conceptual design of the sub-systems to achieve the intended mission. Based on the extracted results, the Armita probe with a mass of 6.9 kg and geometric dimensions of 48 x 38 x 36 cm with a total energy consumption of 112 amp hours will be able to perform the intended mission and satisfy all technical, dimensional and mass requirements well. shows
