A. Rajabi, Noordin Qadiri Massoom, M. Amirifar, S. R. Rouholamini, Pouria Mikaniki, Mohammad Ghorbi, Majid Kamranifar
{"title":"Effects of Injector Pressure Drop on the Performance of a Monopropellant Hydrazine Thruster","authors":"A. Rajabi, Noordin Qadiri Massoom, M. Amirifar, S. R. Rouholamini, Pouria Mikaniki, Mohammad Ghorbi, Majid Kamranifar","doi":"10.30699/jsst.2022.1301","DOIUrl":"https://doi.org/10.30699/jsst.2022.1301","url":null,"abstract":"","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115039120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maryam Salavatifar, Nilofar Mosallaei, A. Salmanian
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{"title":"Heterologous Expression of Shiga-Like Toxin Type 2 in Microgravity Condition","authors":"Maryam Salavatifar, Nilofar Mosallaei, A. Salmanian","doi":"10.30699/jsst.2023.1396","DOIUrl":"https://doi.org/10.30699/jsst.2023.1396","url":null,"abstract":",","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127790416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A study of the effect of microgravity on the endothelial progenitor cells is useful both in understanding cardiac changes in astronauts and in using microgravity as angiogenic stimuli. The aim of the present study was to investigate the effect of microgravity on VEGFR-2 and CD34 angiogenesis markers. Following extraction of progenitor cells from peripheral blood and its confirmation, gene expression was assessed by real-time PCR, and cell viability was assessed by MTT assay. The extracted cells were endothelial progenitor cells in terms of shape and surface markers CD31 and CD144. Microgravity increased the VEGFR-2 gene expression by 3.5 times after 24 hours. CD34 expression increased by 50% after 3 h but reached control level after 24 hours. Microgravity appears to have a positive effect on the expression of angiogenic markers and stimulation of endothelial progenitor cells, and it may be used as a new environment to differentiate these cells into blood vessels and to treat heart disease..
{"title":"Study of the effect of the microgravity on the expression of angiogenesis marker in endothelial progenitor cells","authors":"V. zarrinpour, Zahrs Hajebrahimi","doi":"10.30699/jsst.2023.1334","DOIUrl":"https://doi.org/10.30699/jsst.2023.1334","url":null,"abstract":"A study of the effect of microgravity on the endothelial progenitor cells is useful both in understanding cardiac changes in astronauts and in using microgravity as angiogenic stimuli. The aim of the present study was to investigate the effect of microgravity on VEGFR-2 and CD34 angiogenesis markers. Following extraction of progenitor cells from peripheral blood and its confirmation, gene expression was assessed by real-time PCR, and cell viability was assessed by MTT assay. The extracted cells were endothelial progenitor cells in terms of shape and surface markers CD31 and CD144. Microgravity increased the VEGFR-2 gene expression by 3.5 times after 24 hours. CD34 expression increased by 50% after 3 h but reached control level after 24 hours. Microgravity appears to have a positive effect on the expression of angiogenic markers and stimulation of endothelial progenitor cells, and it may be used as a new environment to differentiate these cells into blood vessels and to treat heart disease..","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115044151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Farajollahi, R. Firuzi, Mohammad Reza Salimi, M. Rostami
{"title":"Numerical study on the effects of nozzle geometry and creating swirly flow inside the injector nozzle on the performance of an engine","authors":"A. Farajollahi, R. Firuzi, Mohammad Reza Salimi, M. Rostami","doi":"10.30699/jsst.2023.1303","DOIUrl":"https://doi.org/10.30699/jsst.2023.1303","url":null,"abstract":"","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129505733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, in order to provide telecommunication coverage for a wide geographical area, the use of a network consisting of an LEO satellite and a Tethered-Balloon equipped with antenna pointing mechanism is proposed. The proposed telecommunication network is able to send the collected data to a mission center outside the covered region and receive the required telecommands, while providing a telecommunication link between the users in the covered region. To control and point the antenna beams towards desired targets, an Adaptive Dynamic Surface Controller is designed. Determining the required operating modes, designing a mode management algorithm and extracting the appropriate reference trajectories for each operating mode are among the discussed issues in this paper. The Uniform Ultimate Boundary (UUB) stability of the closed-loop system is proved and the performance of the control system is studied by simulation. The proposed communication network and control system are able to provide wide telecommunication coverage in remote areas or emergency situations .
{"title":"Extensive Regional Telecommunications Coverage in Emergency Condition using Satellite and Tethered-Balloon Equipped with Antenna Pointing Mechanism – Part 2: Operation Modes and Controller Design","authors":"J. Ranjbar, Mohammad Fathi","doi":"10.30699/jsst.2023.1341","DOIUrl":"https://doi.org/10.30699/jsst.2023.1341","url":null,"abstract":"In this paper, in order to provide telecommunication coverage for a wide geographical area, the use of a network consisting of an LEO satellite and a Tethered-Balloon equipped with antenna pointing mechanism is proposed. The proposed telecommunication network is able to send the collected data to a mission center outside the covered region and receive the required telecommands, while providing a telecommunication link between the users in the covered region. To control and point the antenna beams towards desired targets, an Adaptive Dynamic Surface Controller is designed. Determining the required operating modes, designing a mode management algorithm and extracting the appropriate reference trajectories for each operating mode are among the discussed issues in this paper. The Uniform Ultimate Boundary (UUB) stability of the closed-loop system is proved and the performance of the control system is studied by simulation. The proposed communication network and control system are able to provide wide telecommunication coverage in remote areas or emergency situations .","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122973074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amirhossein Mirzaei, S. H. Jalali Naieni, Ali Arabian Arani
The miss distance analysis of the first-order explicit guidance law (EGL) is carried out using linearized equation of motion in the normalized form in order to obtain normalized miss distance curves. The initial heading error, constant target acceleration, acceleration limit, radome refraction error, and fifth-order binomial control system are considered. Moreover, body rate feedback is added to the explicit guidance law as a well-known classical compensation method of the radome effect as in proportional navigation. The analysis is performed for different values of the power of the alpha function, defined as the time decrease rate of the zero-effort miss to unit control input. As a special case, the EGL with unit power gives the first-order optimal guidance strategy for minimizing the integral of the square of the commanded acceleration during the total flight time. For the performance/stability analysis, the rms miss distance versus turning rate time constant and radome slope can be plotted for different values of the power of alpha function.
{"title":"Miss Distance analysis of First-Order Explicit Guidance Law with/without radome effect","authors":"Amirhossein Mirzaei, S. H. Jalali Naieni, Ali Arabian Arani","doi":"10.30699/jsst.2022.1385","DOIUrl":"https://doi.org/10.30699/jsst.2022.1385","url":null,"abstract":"The miss distance analysis of the first-order explicit guidance law (EGL) is carried out using linearized equation of motion in the normalized form in order to obtain normalized miss distance curves. The initial heading error, constant target acceleration, acceleration limit, radome refraction error, and fifth-order binomial control system are considered. Moreover, body rate feedback is added to the explicit guidance law as a well-known classical compensation method of the radome effect as in proportional navigation. The analysis is performed for different values of the power of the alpha function, defined as the time decrease rate of the zero-effort miss to unit control input. As a special case, the EGL with unit power gives the first-order optimal guidance strategy for minimizing the integral of the square of the commanded acceleration during the total flight time. For the performance/stability analysis, the rms miss distance versus turning rate time constant and radome slope can be plotted for different values of the power of alpha function.","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123179687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Karimpour, J. Sadidi, Seyed Mohammad Tavakoli Saboor
{"title":"Data Augmentation Investigating in improving the performance of deep learning model for building segmentation using aerial images","authors":"S. Karimpour, J. Sadidi, Seyed Mohammad Tavakoli Saboor","doi":"10.30699/jsst.2022.1364","DOIUrl":"https://doi.org/10.30699/jsst.2022.1364","url":null,"abstract":"","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116585817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. R. Rouholamini, M. Amirifar, A. Rajabi, Nooredin Ghadiri Massoom
In this paper, by creating and developing a code based on thermodynamics and gas dynamics equations, the performance characteristics of a 1N hydrazine monopropellant thruster such as thrust force, specific impulse, characteristic exhaust velocity, and propellant mass flow rate have been studied theoretically in terms of reaction chamber temperature. In this regard, by taking into account the adiabatic assumption, the reaction chamber temperature of monopropellant thruster has been analyzed zero-dimensionally using the ammonia dissociation rate as an independent variable under equilibrium and non-equilibrium conditions and it has been analyzed one-dimensionally using the hydrazine and ammonia homogeneous and heterogeneous reaction rate constants. Also, the effect of nozzle throat thermal expansion on reaction chamber pressure, thrust force, and propellant mass flow rate and the effect of reaction chamber pressure on ammonia dissociation rate and consequently on reaction chamber adiabatic temperature under thermodynamic equilibrium conditions have been studied
{"title":"Investigation on Performance Characteristics of Hydrazine Monopropellant Thruster according to Reaction Chamber Adiabatic Temperature","authors":"S. R. Rouholamini, M. Amirifar, A. Rajabi, Nooredin Ghadiri Massoom","doi":"10.30699/jsst.2022.1362","DOIUrl":"https://doi.org/10.30699/jsst.2022.1362","url":null,"abstract":"In this paper, by creating and developing a code based on thermodynamics and gas dynamics equations, the performance characteristics of a 1N hydrazine monopropellant thruster such as thrust force, specific impulse, characteristic exhaust velocity, and propellant mass flow rate have been studied theoretically in terms of reaction chamber temperature. In this regard, by taking into account the adiabatic assumption, the reaction chamber temperature of monopropellant thruster has been analyzed zero-dimensionally using the ammonia dissociation rate as an independent variable under equilibrium and non-equilibrium conditions and it has been analyzed one-dimensionally using the hydrazine and ammonia homogeneous and heterogeneous reaction rate constants. Also, the effect of nozzle throat thermal expansion on reaction chamber pressure, thrust force, and propellant mass flow rate and the effect of reaction chamber pressure on ammonia dissociation rate and consequently on reaction chamber adiabatic temperature under thermodynamic equilibrium conditions have been studied","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133780996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hydrazine monopropellant thrusters are widely used in space missions. The most common use of these thrusters is in reactive control systems. In this research, design and simulation of a single capillary injector and three-hole circular injector plate of a 10N Hydrazine monopropellant thruster were performed. The injector and injector plate were designed based on the mass flow rate. Ansys Fluent software was used to simulate them. Volume of fluid (VOF) method was used to simulate such a flow and turbulence was simulated by k-e model. The characteristics of the injector and injector plate including mass flow rate and average velocity in the injector nozzle were calculated by changing the inlet pressure. The results showed that the injector and the injector plate have the ability to supply the desired mass flow rate of the monopropellant thruster at a known design pressure. Therefore, the final dimensions were selected for the design and construction of the injector. In fact the capillary injector اhas replaced the swirl injector with hollow cone spray used in the previous version of this thruster. The dimension of the chamber was significantly reduced by using the capillary injector, which reduces both the volume of the expensive iridium catalyst and weight of the thruster.
联氨单推进剂推进器在航天任务中有着广泛的应用。这些推进器最常见的用途是在无功控制系统中。本文对10N肼单推进剂推进器的单毛细管喷射器和三孔圆形喷射器板进行了设计和仿真。基于质量流量设计了喷油器和喷油器板。采用Ansys Fluent软件对其进行仿真。采用流体体积法(Volume of fluid, VOF)模拟该流场，采用k-e模型模拟湍流。通过改变进口压力，计算了喷油器和喷油器板的质量流量和喷油器喷嘴内的平均速度。结果表明，在给定的设计压力下，喷射器和喷射器板具有提供单推进剂推进器所需质量流量的能力。因此，喷油器的设计和构造选择了最终尺寸。事实上，毛细管喷射器اhas用空心锥喷射器取代了之前版本的涡流喷射器。通过使用毛细管进样器，大大减小了腔室的尺寸，从而减少了昂贵的铱催化剂的体积和推进器的重量。
{"title":"Design and Simulation of Single Capillary Injector and Circular Injector Plate for a Monopropellant Thruster","authors":"H. Karimaei","doi":"10.30699/jsst.2021.1314","DOIUrl":"https://doi.org/10.30699/jsst.2021.1314","url":null,"abstract":"Hydrazine monopropellant thrusters are widely used in space missions. The most common use of these thrusters is in reactive control systems. In this research, design and simulation of a single capillary injector and three-hole circular injector plate of a 10N Hydrazine monopropellant thruster were performed. The injector and injector plate were designed based on the mass flow rate. Ansys Fluent software was used to simulate them. Volume of fluid (VOF) method was used to simulate such a flow and turbulence was simulated by k-e model. The characteristics of the injector and injector plate including mass flow rate and average velocity in the injector nozzle were calculated by changing the inlet pressure. The results showed that the injector and the injector plate have the ability to supply the desired mass flow rate of the monopropellant thruster at a known design pressure. Therefore, the final dimensions were selected for the design and construction of the injector. In fact the capillary injector اhas replaced the swirl injector with hollow cone spray used in the previous version of this thruster. The dimension of the chamber was significantly reduced by using the capillary injector, which reduces both the volume of the expensive iridium catalyst and weight of the thruster.","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129759038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, in addition to investigation and analyzing the dynamic model of a maneuver target, a new method based on the Interaction Multiple Model (IMM) method is presented to solve the tracking problem in presence of measurement noise. In this procedure, two models are used along with an extended Kalman filter for each model, for estimation of the states related to stochastic target model. To this end, a specific weight is calculated adaptively for each model and the final estimation of the target is obtained from the weighted sum of the modes related to each model. In this paper, second order Markov models are used to better describe the system behavior which leads to a decrease in the number of required motion models. This means that the previous two models are used to decide on the next model, and a much better algorithm is provided than the first-order IMM algorithm
{"title":"Bearing only tracking for maneuver target using nonlinear second-order Markov model","authors":"M. Ebrahimi, A. F. Ehyaei","doi":"10.30699/jsst.2022.1361","DOIUrl":"https://doi.org/10.30699/jsst.2022.1361","url":null,"abstract":"In this paper, in addition to investigation and analyzing the dynamic model of a maneuver target, a new method based on the Interaction Multiple Model (IMM) method is presented to solve the tracking problem in presence of measurement noise. In this procedure, two models are used along with an extended Kalman filter for each model, for estimation of the states related to stochastic target model. To this end, a specific weight is calculated adaptively for each model and the final estimation of the target is obtained from the weighted sum of the modes related to each model. In this paper, second order Markov models are used to better describe the system behavior which leads to a decrease in the number of required motion models. This means that the previous two models are used to decide on the next model, and a much better algorithm is provided than the first-order IMM algorithm","PeriodicalId":272394,"journal":{"name":"Journal of Space Science and Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129409264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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