bluuebunny/crossref_metadata_2025 huggingface dataset:
EXPLORING THE EFFECT OF Actinidia deliciosa EXTRACT FOR SKIN REVITALIZATION
Authors: RAFIQUE SADIA , IRSHAD KANWAL , AFSHEEN NADIA , RIAZ ROMANA , MEER SIDRA , KAUSAR RIZWANA , QURESHI MUHAMMAD SHERAZ , KHAN MUHAMMAD ISHFAQ
Published: July 2022

Background: The research project was designed to prepare the emulgel (O/W) from extract of Actinidia deliciosa to evaluate its effects on the skin of human.

Aim: To evaluate emulgels as a base prepared from fruit Actinidia deliciosa which was expected to reduce the erythema, melanin and sebum level of skin as well as to increase the moisture content in the skin and increase elasticity.

Methods: The emulgels (O/W) prepared from Actinidia deliciosa fruit extract. The prepared formulation contained 5% extract and base (extract exclude) were applied for the period of 3 months on the cheeks of 13 healthy female volunteer. The melanin, erythema, elasticity, moisture contents and sebum of skin were measured at baseline and then evaluate the effect of prepared formulation after every 14 days during the whole experimental period.

Results: The results obtained from formulation gel against base gel for skin melanin, erythema, sebum, elasticity and moisture contents showed the significant effect.

Conclusions: The prepared formulation was declared to be suitable anti-wrinkle, anti-aging, skin whitening agent and used for the treatment of many different dermatological preparations such as acne.
Dimensions and Components of Brand-Based Human Resources Management in Pharmaceutical Companies: A Case Study
Authors: Hassanpoor Akbar , Jafarniya Saeed , Vakili Yousef , Taghavi Leila
Published: July 2022

: Currently, in organizations, customer satisfaction and focus on successful sales are not enough to improve the organization’s assets and maintain a competitive position in the market. Therefore, companies should adopt the necessary measures and strategies to attract and preserve effective human resources. Without the power of efficient human resources, an organization is unable to create transformation, development, and excellence and achieve a strategic model and the set goal. For this purpose, there should be management that leads the organization and creates an efficient structure for the production of human resources. Brand human resources management is a differentiation in the core of human capital management strategy. The main function of brand-based human resources management is to attract potential workforce outside an organization and maintain talent within an organization. Human resources management can play an important role in the success of an organization’s branding; however, it has received less attention. This study aimed to explore the perception of the concept of brand-based human resources and to present its dimensions and components; in terms of purpose, data collection, and data certainty, this study was applied-developmental, descriptive, and exploratory, respectively. The statistical population included written sources or texts related to brand-based human resources management that were available. Moreover, the sampling method in this study was purposeful. The main findings of this study included identifying the dimensions and components of brand-based human resources management in 17 basic themes, 8 organizing themes (components), and 3 comprehensive themes (dimensions). Based on the findings of this study, it is possible to evaluate companies’ brand-oriented level of human resources management. Accordingly, action is taken to plan to improve weak aspects.
A Demographics Analysis of IgE- and Non-IgE-mediated Food Allergies in Children
Authors: Norolahi Mohammad , Hematyar Masoumeh , Pouyanfar Rahman , Hashemitari Seyed Karen , Darougar Sepideh
Published: July 2022

Background: There are three broad types of food allergies, including IgE-mediated reactions, non-IgE-mediated reactions, and mixed reactions. The onset of IgE-mediated food allergies is usually rapid and can sometimes lead to serious illness. Non-IgE-mediated and mixed types of food allergies can cause significant morbidity as a result of chronic disease. Objectives: This study aimed to compare various types of food allergies and discuss the basis of their different presentations. Methods: This study was conducted on children aged 2 - 12 years old with signs or symptoms of food allergy in the allergy clinics of Azad University Hospitals, Tehran, Iran, from January 2019 to January 2020. Food allergy was evaluated in these patients by careful history, physical exam, skin prick test, and atopy patch test. Results: A positive family history of atopy was detected in the first-degree relatives of 82 (63%) patients. All the children were exclusively breastfed at the beginning. A total of 61 patients had positive skin prick test (SPT), and 68 patients had positive atopy patch test (APT) results. Among food allergens, a significant correlation was detected between positive atopic patch test results and hypersensitivity reactions to cow’s milk (P value = 0.001), beef (0.002), and tomato (0.04). There was the same significant correlation between positive skin prick test results, allergens, and wheat (P value = 0.01). Conclusions: Although skin prick and atopy patch tests may help identify the culprit foods, oral food challenges are the mainstay of the diagnosis.
Topomineralogía de la província de León 3
Authors: Mata Perelló Josep Maria , Sanz Balagué Joaquim
Published: July 2022

Con este número, continuaremos el tratamiento de la TOPOMINERALOGIA DE LA PROVINCIA DE LEÓN: o lo que es lo mismo: LOS MINERALES Y SUS YACIMIENTOS EN LA PROVÍNCIA DE LEÖN

Así, esta serie de publicaciones dedicadas a las TOPOMINERALOGIAS PROVINCIALES, ya hemos dedicado diversos números a varias provincias española. En los últimos números publicados, nos hemos referido estado refiriendo a esta provincia de León y en concreto al Partido Judicial de León en los números 34 i 35.

En esta serie, queremos plasmar los resultados de unos trabajos de campo, realizados durante los años 1992 y 2000, recorriendo pueblos y campos de la toda la Península Ibérica (de España y de Portugal) y también del sur de Francia. Estos trabajos han permanecido ocultos hasta ahora. Y ahora los publicamos, para que puedan servir de base para nuevas experiencias en el campo.

Ahora, en este número (CANTIL 036), nos centraremos en las localidades de la demarcación del actual partido judicial de LA BAÑEZA, que corresponde a la antigua TIERRA DE LA BAÑEZA.

Posteriormente, nos iremos refiriendo al resto de los partidos judiciales leoneses, en siguientes números.

En cada caso, en la FICHA EXCEL (elaborada por Antonieta SANTACREU), daremos los siguientes daros de cada indicio:

- LOCALIDAD. A menudo indicaremos el agregado (en este caso, con el nombre del municipio, entre paréntesis)

- PARAJE (con las coordenadas UTM X e Y y a menudo la Z)

- TIPOLOGÍA

- Nª DEL MAPA EN QUE SE HALLA (a escala 1:50.000)

- MINERALES ENCONTRADOS

Evidentemente, podríamos ”vestir” estos datos con más detalles, pero en aras a la efectividad, nos hemos decantado por la sencillez de esta exposición de los datos otrora obtenidos y revisados a menudo en el campo, tras sucesivas investigaciones sobre el terreno.
Topomineralogía de la provincia de Badajoz 3
Authors: Mata Perelló Josep Maria , Sanz Balagué Joaquim
Published: July 2022

Con este número, seguiremos con el tratamiento de la TOPOMINERALOGIA DE LA PROVINCIA DE BADAJOZ: o lo que es lo mismo: LOS MINERALES Y SUS YACIMIENTOS EN LA PROVÍNCIA DE BADAJOZ

Así, esta serie de publicaciones dedicadas a las TOPOMINERALOGIAS PROVINCIALES, ya hemos dedicado diversos números a varias provincias españolas.

En esta serie, queremos plasmar los resultados de unos trabajos de campo, realizados durante los años 1992 y 2000, recorriendo pueblos y campos de la toda la Península Ibérica (de España y de Portugal) y también del sur de Francia. Estos trabajos han permanecido ocultos hasta ahora. Y ahora los publicamos, para que puedan servir de base para nuevas experiencias en el campo.

Ahora, en este número (CANTIL 045), nos centraremos en las localidades de la demarcación del actual partido judicial de BADAJOZ de esta provincia extremeña. Y también al de COSTUERA, de la misma provincia.

En cada caso, en la FICHA EXCEL (elaborada por Antonieta SANTACREU), daremos los siguientes daros de cada indicio:

- LOCALIDAD. A menudo indicaremos el agregado (en este caso, con el nombre del municipio, entre paréntesis)

- PARAJE (con las coordenadas UTM X e Y y a menudo la Z)

- TIPOLOGÍA

- Nª DEL MAPA EN QUE SE HALLA (a escala 1:50.000)

- MINERALES ENCONTRADOS

Evidentemente, podríamos ”vestir” estos datos con más detalles, pero en aras a la efectividad, nos hemos decantado por la sencillez de esta exposición de los datos otrora obtenidos y revisados a menudo en el campo, tras sucesivas investigaciones sobre el terreno.
Topomineralogía de la provincia de Badajoz 6
Authors: Mata Perelló Josep Maria , Sanz Balagué Joaquim
Published: July 2022

Con este número, seguiremos con el tratamiento de la TOPOMINERALOGIA DE LA PROVINCIA DE BADAJOZ: o lo que es lo mismo: LOS MINERALES Y SUS YACIMIENTOS EN LA PROVÍNCIA DE BADAJOZ

Así, esta serie de publicaciones dedicadas a las TOPOMINERALOGIAS PROVINCIALES, ya hemos dedicado diversos números a varias provincias españolas.

En esta serie, queremos plasmar los resultados de unos trabajos de campo, realizados durante los años 1992 y 2000, recorriendo pueblos y campos de la toda la Península Ibérica (de España y de Portugal) y también del sur de Francia. Estos trabajos han permanecido ocultos hasta ahora. Y ahora los publicamos, para que puedan servir de base para nuevas experiencias en el campo.

Ahora, en este número (CANTIL 048), nos centraremos en las localidades de la demarcación del actual partido judicial de HERRERA DEL DUQUE de esta provincia extremeña.

En cada caso, en la FICHA EXCEL (elaborada por Antonieta SANTACREU), daremos los siguientes daros de cada indicio:

- LOCALIDAD. A menudo indicaremos el agregado (en este caso, con el nombre del municipio, entre paréntesis)

- PARAJE (con las coordenadas UTM X e Y y a menudo la Z)

- TIPOLOGÍA

- Nª DEL MAPA EN QUE SE HALLA (a escala 1:50.000)

- MINERALES ENCONTRADOS

Evidentemente, podríamos ”vestir” estos datos con más detalles, pero en aras a la efectividad, nos hemos decantado por la sencillez de esta exposición de los datos otrora obtenidos y revisados a menudo en el campo, tras sucesivas investigaciones sobre el terreno.
Mission analysis of nanosatellite constellations with OpenSatKit
Authors: Sermanoukian Molina Iván , Montilla Rodríguez Lluís , González Díez David , Sureda Anfres Miquel , Mata Diaz Jorge , Alins Delgado Juan José
Published: July 2022

CubeSat reliability is still considered an obstacle due to the sizeable fail rates generally attributed to the dead-on-arrival cases and early subsystem malfunctions. Thus, as CubeSats' primary purpose moves from technological demonstrations and university projects to missions where a significant risk of failure is not acceptable, an inexpensive method to emulate low Earth orbit constellations is being researched. The results presented have been developed in the framework of the PLATHON research project, which intends to develop a hardware-in-the-loop emulation platform for nanosatellite constellations with optical inter-satellite communication and ground-to-satellite links. Consequently, a crucial aspect of this project is to have a sufficiently precise orbital propagator with real-time manoeuvring control and graphical representation. NASA's OpenSatKit, a multi-faceted open-source platform with an inbuilt propagator known as 42, has been chosen to analyse the programme's feasibility in order to create a constellation testing bench. As an initial development of a software-in-the-loop application, the pre- processing of files has been automated; enhanced Attitude Determination and Control System manoeuvres have been added and configured through bidirectional socket interfaces, and the results format has been modified to be easily post-processed with MATLAB and Simulink
Design and methodology for a remote sensing course
Authors: Sitjar Suñer Josep
Published: July 2022

Remote sensing offers Geographic Information Systems specialists the possibility of integrating useful and powerful information into their analyses. As at least a basic knowledge of remote sensing principles and methodologies are desirable for anyone working in the geospatial industry, we include this competence as a mandatory subject in the curricula of our online master’s degree in GIS analysis. The topics of this remote sensing course have been selected based on our experience in the sector, but also with the support of tools like the body of knowledge developed by the GI2NK and EO4GEO projects. These applications can be very useful for anyone starting with the creation of new courses, as they take into consideration the recommendations of experts related to different sectors: from university to private companies, and also from the public sector. The course is fundamentally based on practical work, but since it is introductory and most of the students are not familiar with the principles of remote sensing, it is essential for them to start understanding basic concepts such as electromagnetic radiation, electromagnetic spectrum, spectral signature, bands, etc. After that, they are prepared to start searching the best images for a specific project, perform image enhancements and corrections, compute indices and apply supervised and unsupervised classifications. During the course, students are encouraged to use open-source software to develop the mandatory activities and the optional ones. Most of the tutorials are based on QuantumGIS and some of its main extensions to work with raster data and remote sensing images, but there are also tutorials based on GRASS Gis and SNAP. Nevertheless, students have total freedom to choose any available software (open-source or not) to perform the mandatory activities, and the tutor is open to resolving doubts about them. Finally, the module is designed to practice with Copernicus and Landsat images. The use of these free catalogues offers the possibility to analyse phenomena from all over the world without cost, and it empowers students to carry out their own projects more economically. Also, the historical series of Landsat Images is very useful to evaluate changes over long periods of time
TOLOSAT project: Gravimetry and communication
Authors: Knight Tristan , Rousse Axel , Allietta Clémence , Bérat Benjamin
Published: July 2022

The use of Constellations for weather science, security and disaster monitoring is a major challenge for space application services. Satellite to satellite communication using existing constellations has not been extensively explored yet. It can improve the communication times for small-satellite missions which have limited access to ground stations. Thus, a mission to demonstrate the feasibility of this link is required. Another element of interest in space application is Earth Observation, especially in the context of Climate Change. Gravimetry allows an understanding of mass transport in the Earth System through the remote sensing of the time variation of the Earth gravity field. CubeSats are low-cost small-scale and hence lower risk solutions to Earth Observation missions. University CubeSats have shown their success in demonstration and scientific missions, and have a great potential in providing students with practice and application on real space systems. In this context, the student associations ASTRE and SUPAERO CubeSat Club have joined in a CubeSat program called TOLOSAT, with the hope of demonstrating such technologies. Gathering 70 students from Toulouse, the team was split into subsystems in accordance with the concurrent engineering principles. The work performed followed recommendations from experts from the French National Centre for Space Studies (CNES) and the industry. The TOLOSAT payloads have to test and demonstrate new means of measuring gravity and addressing communication issues. Firstly, for the gravimetry mission, our approach relies solely on GNSS to compute the gravity field, avoiding expensive gravimeters. For the communication mission: the Iridium constellation will be used as an intermediate between the CubeSat and the ground station. Off-the-shelf components such as patch antennas are planned to prove their efficiency in orbit. This would improve the coverage and the communication window. The preliminary design was completed. TOLOSAT was designed as a 3-unit nanosatellite, on a 97.4° inclined, 500km high orbit. Margins were also ensured to allow a third payload to be defined in the future, that will be used for finance and partnerships. Detailed designs are still required, but the educational purposes have been fulfilled, in terms of discovery of the development of space missions as well as in the teamwork culture. The team is now moving on to a new phase, dedicated to a more detailed conception with an on-going focus on the introduction to students to technical - but not only - fields of knowledge applied to space systems
Analysis of planetary spacecraft images with SPICE
Authors: Peña Mercade Teresa , Soria Guerrero Manel , Betriu Paula , García Melendo Enrique José
Published: July 2022

Spacecraft images are an invaluable source of information in Planetary Science. However, they must be processed and the initial stage is to navigate them, i.e., determine the longitude and latitude coordinates of each pixel on the image plane. The main goal of the present work is to develop an open-source tool to do so. It will be independent of proprietary software and implemented in a widely used language (Java, Python). It will be able to analyse planetary images taken by different spacecraft, such as New Horizons, Cassini or Voyager, with minimal user intervention. Here we present the first steps of the process illustrating the techniques to navigate an image of an ellipsoidal body, obtained from mission kernels using NASA Jet Propulsion Laboratory SPICE library, considering that the attitude and position of the spacecraft are available; correct the camera attitude information; determine the image resolution for each pixel; and combine different images of a body to generate mosaics with high resolution
The advanced Master of Space Studies at KU Leuven and Ghent University: Trends and tendencies in the program demographics
Authors: Sana Hugues , Gielen Clio
Published: July 2022

Organized by KU Leuven and Ghent University, two leading Belgian universities, the Master of Space Studies is an interdisciplinary post-master program that aims to equip students with the skills they need to initiate a career in the space sector. Beyond the deepening of their initial expertise, the program exposes the participating students to a broad range of topics, from human science (space law and policy, international organizations, project management, ...), to technical science (space missions, spacecraft and payload engineering, satellite telecommunications, ...), and exact sciences (Earth and Space observations, medical sciences, human explorations, ...) with the aim to provide the students with a broad overview of the interdisciplinary expertise required by many space projects. Initiated in the late 2000s, the program has served as a gateway into the space sector for over 100 students since its creation. After a brief introduction to the program, we present a programmatic analysis, based on quantitative and qualitative surveys of students and alumni. We present the demographic, career tracks and current professional situations of students in the last 10 years, allowing us to identify trends that affects tertiary education to space sector. We conclude by briefly highlighting other ongoing space education activities, from the Belgian antenna of ESERO to the involvement of students in CubeSpec, a 6U CubeSat platform selected as ESA in-flight demonstrator to enable low-cost versatile spectroscopy of astronomical targets
Design and optimization of a rocket structure following the requirements for the European Rocketry Challenge (EUROC) to be fabricated using additive manufacturing
Authors: Grau Rifà Jordi
Published: July 2022

Amateur rocket structures are usually made of composite materials, wood or aluminium, their internal geometries and interfaces are usually restricted by the available manufacturing techniques. However, with the appearance of the additive manufacturing sector new possibilities arise for the design of the structures and its complexity. In this paper a PA-12 and glass fibre composite structure for the Phobos rocket is designed which the UPC Space Program aims to use to participate in the European Rocketry challenge. The Phobos rocket structure is designed and optimized to be fabricated using additive manufacturing by Hewlett-Packard. The structure is designed using a lattice approach to obtain a PA-12 skeleton which is then reinforced with a skin of glass fibre composite. Moreover, to obtain the desired structure an optimization methodology is set using a design loop in which the critical section of the rocket is parametrically optimized to reach the equivalent traditional structure performance. The structure is optimized in the size of the lattice geometry and in the thickness of the skin as parameters. To do so, the critical load during the flight of the rocket is identified and translated to the Nastran environment to run a parametric optimization of the structural model. The optimized geometry is then extended to the rest of the rocket to obtain the overall optimized structure. In addition, several analyses are conducted to validate the structure behaviour for the different load cases. Finally, both the optimized critical case and the overall optimized structure are compared to traditional design structures to obtain conclusive results about the use and limitations of the available additive technology and its materials
An investigation into cold weld adhesion for spacecraft repair after a space debris impact using space education based sub-orbital sounding rocket platform
Authors: Wylie Mark , Barilaro Leonardo
Published: July 2022

It has been observed that similar metallic materials, when in contact and undergoing relative displacements, can fuse or weld. In standard atmospheric conditions it is not common but in the space environment the inability of the surface interfaces to re-oxide after abrasive contact is hindered, atomic diffusion of the metal occurs, and this can lead to fusion. Oscillatory motion and Hertzian contact stress between the two surfaces plays a major role in the strength of the cold welded joint. It has been shown that the action of a low fretting load can almost double the adhesion force under cyclic loading even in terrestrial atmospheric conditions. In space, cold welding was first identified in the 1960’s as an adverse reaction. It has been attributed to anomalies and failures of deployable mechanisms. Other research has alluded to the potential of this phenomena for use in spacecraft repair in space. Examples where this may hold promise is repair of a spacecraft hull breach after hypervelocity impacts due to micrometeoroids or orbital debris. This research proposes an investigation into cold welding for use in spacecraft hull repair. The research intends to qualify an experimental apparatus to TRL 4 using a sub-orbital sounding rocket platform. A joint research effort between the Aerospace, Mechanical and Electronic Department at I.T. Carlow, Ireland, the Department of Aviation at Malta College of Arts, Science, and Technology, Malta is underway. The project aims at developing a test apparatus to apply a number of custom patches to simulated hypervelocity spacecraft hull breaches and investigate the adhesion properties during re-entry for a range of mechanical application conditions. A number of chambers may be tested and monitored using pressure transducers. After Phase 1 (terrestrial development and validation using a vacuum chamber), there will be an application to education based space programmes such as the one offered by the European Space Agency (REXUS). The core of the activity will be the design and testing of the experimental payload, simulating hull breaches, deployment the repair patch and monitoring of its performance during re-entry (Phase 2). The recovery of the payload will allow further metallurgical analysis of the cold welded joint (Phase 3). A conceptual 3-D model of the payload has been developed and is presented here. The data acquired from the sub-orbital flight experiment will test the validity of the hypothesis for use of cold welding for spacecraft hull repair but will also detail the development and implementation of mock hypervelocity impacts to rocket skin for the purposes of simulating hull breaches in the space environment
Supporting an ISS experiment as PhD students: a case study of the PARTICLE VIBRATION project
Authors: Crewdson Georgie , Boaro Alessio , Kerr Monica , Lappa Marcello
Published: July 2022

This paper provides an insight into the involvement of two PhD students in the PARTICLE VIBRATION project, a multiphase fluid experiment, also known as, “Thermovibrationally-driven Particle self-Assembly and Ordering mechanisms in Low grAvity” (T-PAOLA) to be launched on the International Space Station by the end of 2022. The project aims to identify self-organization phenomena in dispersed phase flows when vibrations are applied to the system. It will therefore underpin the development of new contactless particle manipulations and materials processing strategies. In this short paper, the work of two PhD candidates, working within the T-PAOLA project framework, is discussed. In doing so, the various research activities undertaken are highlighted, both experimental and numerical, as is the peripheral or supporting research being undertaken by both students in order to expand the scope of the project and identify new lines of enquiry regarding convection-based control mechanisms
The Sat-Comms Game: teaching a complex subject for interdisciplinary audiences
Authors: Iliffe Paul
Published: July 2022

This paper addresses general space education for interdisciplinary audiences. In particular, this paper considers education in the field of Satellite Telecommunications (Sat-Comms). The challenge in presenting the field of sat-comms for effective learning is two-fold. Firstly, this field is interdisciplinary, the disciplines are coupled, and it is complex. Secondly, the typical audiences for this subject often have diverse backgrounds. Hence, a suitable teaching strategy is required, so that all students can learn from a training session. Publicly available sat-comms training is largely engineering focused. This study could not find suitable training for the purpose of interdisciplinary sat-comms education. Hence, to address this absence in available training, the author has created a workshop, which provides sat-comms education to interdisciplinary audiences. The workshop was empirically developed from the author’s experience at Inmarsat and at the International Space University. The workshop uses elements from Constructivist, Behaviourism, Cognitive, Connectivism, and Experiential learning theories. Furthermore, it was designed to be taught in person and online. The Sat-Comms Game was first trialled in an online format in 2021. The workshop worked well in engaging the participants during the session. Additionally, feedback on the workshop was positive. Hence, this trial indicated that the workshop could function logistically and engage people pedagogically. The author intends to conduct further trials and corresponding assessment methods to gauge the pedagogic effectiveness
Developing a 3U CubeSat Engineering Model - FlatSat & Chassis Design
Authors: Crofts William , Langer Mattias , Bolland Alex , Uddin Tahrim , Biquet Chiara , Hopkins Eduard , Bassi Jai , Ing Myles , Hunter Anderson Julia
Published: July 2022

WUSAT-3 is a 3U CubeSat being designed to carry an experimental RF signal direction finding payload in Low Earth Orbit (LEO). Successful outcome of this experiment could lead to significant benefits for the field of wildlife monitoring from Space. Commercial adoption of this process would enable the development and use of much smaller, lighter RF tracking tags, which in turn would considerably increase the potential range of species that could be tracked by Satellites. The effect of the Covid-19 pandemic lockdowns has limited physical progress over the past 18 months, but the team continues to gain enormous experience and motivation from pursuing this exciting project with a very real-world mission. A recent return to near-normal working patterns has enabled the team to fully engage with the practicalities of progressing the previously produced WUSAT-3 Configuration Model, towards a testable Engineering Model. This paper outlines the development of both the initial chassis prototype (including mechanisms) and a subsystem FlatSat as a first stage towards building the complete Engineering Model. The chassis prototype was required to meet all the requirements of the FYS Design Specification [1], the NanoRacks CubeSat ICD [2], the CubeSat Design Specification [3] and those features identified by the outcomes of the WUSAT-3 Configuration Model. The FlatSat was required to include all subsystems capable of being constructed and tested without the availability of certain proprietary items that will be purchased later. The function and interface of these items, where it was necessary for the purpose of testing the assembled subsystem units that were available, was met by the design and inclusion of temporary substitute arrangements that provided similar performance. Systems Engineering methodologies were employed throughout as a means of ensuring that the design features of both chassis and FlatSat met all necessary requirements
Design and calibration process of solar sensors for small satellite missions
Authors: Porras Hermoso Angel , Alfonso Corcuera Daniel , Piqueras Javier , Roibás Millán Elena , Cubas Javier , Pérez Álvarez Javier , Pindado Santiago
Published: July 2022

In combination with magnetometers, solar sensors are one of the most used instruments for determining the attitude of small satellites. These devices use the photoelectric effect to produce an electrical current. This electrical current, or the voltage associated with the electrical circuit of the solar sensor, is measured in order to compute the angle of incident of the sun with the normal direction of the sensor. Then, together with the computed angles of other solar sensors on different faces of the satellite, the sun's direction in relation to a spacecraft can be calculated. Solar sensors are simple devices whose low-cost design based on photodiodes can be developed by students. During the design and fabrication process of a solar sensor, one of the most important tasks is the accurate estimation of the sensor response in the space radiative environment. It is possible to simulate the Sun’s radiation spectrum, but the equipment and facilities needed are costly for a university project. In this paper, the design and calibration process of satellite solar sensors carried out together by students and teachers from the Master's degree in Space Systems (MUSE) from the Universidad Politécnica de Madrid is described. The process uses a calibration method that calibrates the photodiodes for space use without simulating the Sun’s radiation spectrum in the laboratory
EIRFLAT-1: A FlatSat platform for the development and testing of the 2U CubeSat EIRSAT-1
Authors: Reilly Jack , Murphy David , Doyle Maeve , Walsh Sarah , Akarapu Sai Krishna , De Faoite Daithi , Dunwoody Rachel , Erkal Jessica , Finneran Gabriel , Mangan Joseph , Marshall Fergal , Salmon Lána , Somers Eoghan , Thompson Joseph , Ulyanov Alexey , Hanlon Lorraine , McKeown David , O’Connor William , Wall Ronan , McBreen Sheila
Published: July 2022

The Educational Irish Research Satellite (EIRSAT-1) is a 2U CubeSat being designed, built and tested at University College Dublin. A FlatSat platform known as EIRFLAT-1 has been constructed to enable the testing and development of the CubeSat. EIRFLAT-1 facilitates the electrical connections between CubeSat components while leaving key interfaces accessible for test equipment and allowing for the hot swapping of components. Commercial Off The Shelf and in-house developed hardware has been tested using EIRFLAT-1 at component, subsystem and full system level. In addition, the FlatSat has been used for flight software development. This paper describes the design of EIRFLAT-1 including electrical and mechanical components and additional ground support equipment developed to assist in the testing and development activities. EIRFLAT-1 has proven to be an invaluable tool for testing and has led to the discovery of issues and unexpected behaviour with flight hardware which would have contributed to schedule delays if undiscovered until after the satellite was assembled. Moreover, EIRFLAT-1 facilitated early and incremental testing of both software and operations procedures. The schematics for the electrical design of EIRFLAT-1, which is compatible with all CubeSat Kit PC/104 components, has been made publicly available for use by other educational CubeSat teams
Potential application of a measurement tool for quality assurance of E-Learning content to a new MSc in Aerospace Engineering
Authors: Barilaro Özlem Başman , Cardona Mario
Published: July 2022

While witnessing how rapidly and frequently the human life-sustaining structure of society has changed from the past to modern times, the effects of the Covid-19 pandemic presented us a unique challenge, moving a considerable part of our life more than ever online and showing us the signs that a new era has begun. While the access to information is enormous, there is a lack of proper skills in selecting the best options available to upgrade one’s educational status. Considering how fast education tools are evolving, it has become important to carry out new studies in order to increase and boost the Quality Assurance for E-learning processes in Education. In this context, recently in Malta a new Aerospace Programme kicked off through an MSc in Aerospace Engineering. This Master's has been structured as part-time and online, aiming to attract undergraduates and professionals in aeronautics from Europe, Asia and Africa, providing the skills required by national and international aerospace companies. For these reasons, the course has been chosen as a test case for the potential application of a measurement tool for its E-Learning content quality assurance. This paper describes the preliminary analysis to assess the main Quality Measurement parameter. An uncertainty parameter will be associated with the measurement, which will be improved with the increasing size of the statistical sample and iterations. The uncertainty parameter includes measurement errors, sampling errors, variability, use of surrogate data and the combined effect of assumptions that will be necessary to do in the preliminary phase due to the novelty of the study. Projections suggest that in the proposed study case of the MSc in Aerospace Engineering, the Quality Measurement parameter value will increase in the next few years, thanks to continuous investments, the sharpening of teaching and learning tools, and the growth of interest from the Maltese aerospace sector; it is expected that the uncertainty of the model will similarly decrease
Hypergravity induces changes in physiology, gene expression and epigenetics in zebrafish
Authors: Salazar Moscoso Marcela , Joly Ruiz Castellanos Silvia , Anglada Escudé Guillem , Ribas Cabezas Laia
Published: July 2022

All living organisms that inhabit Earth have evolved under a common value of gravity, which amounts to an acceleration of 9.81 m/s2 at mean sea level. Changes on it could cause important alterations that affect vital biological functions. The crescent interest in spatial exploration has opened the question of how exactly these changes in gravity would affect Earth life forms on space environments. This work is the result of a collaborative co-supervision of a master thesis between experts in the area of space sciences and biology, and it can serve as a case study for training experts in such interdisciplinary environments. In particular, we focus on the effect of gravity as a pressure factor in the development of zebrafish (Danio rerio) in the larval stage as a model organism using up-to-date (genomic and epigenetic) techniques. Given the high cost of any experiment in true low gravity (which would require a space launch), we performed an initial experiment in hypergravity to develop the methodologies and identify good (epi)genetic markers of the effect of gravity in our model organism. Previous studies in zebrafish have shown how alteration in gravity effects the development and the gene expression of important regulatory genes. For this study, we firstly customized a small laboratory scale centrifuge to study changes in fish physiology together with changes at molecular levels. We exposed zebrafish larvae from 0 to 6 days post fertilization to the simulated hypergravity (SHG) (100 rpm  3g). After 6 days of hypergravity exposition the larvae showed changes in their swimming and flotation patterns, and presented corporal alterations. Then, we assessed gene expression of genes implicated in important biological processes, (e.g., epigenetics), and an upregulation were observed when compared to the control. Taken together, these preliminary findings show how gravity alterations could affect some basic biological responses, and illustrate the potential of developing new science cases to be developed by students at postgraduate level (MSc and beyond) in a multidisciplinary environment
Development and testing of the 3U+ CubeSat PCDU for SOURCE
Authors: Waizenegger Kevin , Papanikolaou Athanasios , Rudolf Moritz , Koller Markus , Klinkner Sabine
Published: July 2022

SOURCE (Stuttgart Operated University CubeSat for Evaluation and Education) is a 3U+ re-search CubeSat that is being developed by students at the University of Stuttgart in coopera-tion with the Institute for Space Systems and the Small Satellite Student Society KSat e.V.. The objectives include technology demonstrations, atmospheric research and the investigation of satellite demise while also serving as an educational program. SOURCE was selected by ESA's "Fly your Satellite" program and is currently in Phase D. The electrical power supply system combines commercial off-the-shelf parts with self-devel-oped units to meet the requirements of the payloads. The solar array configuration and Power Conditioning and Distribution Unit (PCDU) are self-developed, while the battery is a commer-cial product. A total of 56 solar cells provides up to 32W under ideal conditions, which can be stored in a 75Wh space-qualified lithium-ion battery. To maximise the power output of the solar cells, maximum power point tracking is performed by the PCDU. This is controlled by a radiation hardened microcontroller. The PCDU provides regulated 3.3V, 5V and unregulated battery voltage to the subsystems with 32 switchable outputs, 27 of which are latch-up current protected. The microcontroller controls these individual output channels and the switching between the various CubeSat modes as commanded by the on-board computer. Additionally, every output channel power consumption is monitored for overcurrents. The PCDU functions as a watchdog by checking the health of the on-board computer, rebooting it in case of a failure. High priority commands can be sent directly to the PCDU from the ground via the communication system, bypassing the on-board computer. These can reset either the communication subsystem, the on-board computer or the entire satellite. Four hybrid inhibits, using a combination of mechanical switches and FETs are integrated in the PCDU, replacing the usual fully mechanical design. Three are used to deactivate the satellite in the deployer configuration and the fourth is a remove-before-flight inhibit. An engineering model was manufactured during phase C and is being tested functionally, en-vironmentally and for performance. This paper presents the detailed design of the PCDU, the acquired test results and outlines issues encountered during the tests
Development of a CubeSat CLIMBing to the Van-Allen belt
Authors: Eschelmüller V. , Stren A. , Issa M. , Bauer J. , Goswami A. , Vitztum E. , Repän K. , Treberspurg W. , Scharlemann C.
Published: July 2022

Based on its successful CubeSat mission PEGASUS, the University of Applied Sciences Wiener Neustadt (FHWN) is preparing its new CubeSat mission called CLIMB. CLIMB is a 3U CubeSat that will be launched to a low, circular orbit of about 500 km. Using a Field Emission Electric Propulsion (FEEP) system commercialized by the company ENPULSION, the satellite will be lifted to an elliptical orbit with its apogee around 1000 km – well inside the inner Van Allen belt. During its 1.5 yearlong ascent and its operation in the Van Allen belt, the satellite will continuously monitor the space radiation with a RadFET dosimeter payload and the impact on CLIMB’s subsystems. Comparisons with radiation testing on ground will allow the assessment of the capability of ground tests to predict effects of space radiation on CubeSat subsystems. The operation of the propulsion system will raise the satellite’s apogee on average 16 times a day. A comprehensive analysis has been conducted to assess its collision probability throughout its mission time. Using various tools, provided by ESA (CROC, MASTER and the DRAMA ARES python package), the collision probability for the entire mission duration (~3 years) was calculated to be 3.38 × 10-5, i.e. a magnitude smaller than the requested probability of 10-4. The second payload of CLIMB is an anisotropic magnetoresistance (AMR) magnetometer with a, for CubeSats high, sensitivity of about 10 nT RMS. The first results of measurements with this COTS based magnetometer are presented as well as experimental assessments of the satellite’s magnetic cleanliness. The benign thermal conditions on CubeSats operating close to Earth are complicated by the relatively high-power propulsion system onboard CLIMB. Detailed numerical analysis (ANSYS, ESATAN) and experimental verifications resulted in the identification of possible methods to deal with up to 18 W of dissipated electric power. The main heat sources are the thruster and the battery unit, during thruster operation
Improved sensor fusion for flying laptop based on a multiplicative EKF
Authors: Von Arnim Maximilian , Gaisser Steffen , Klinkner Sabine
Published: July 2022

Flying Laptop is a small satellite carrying an optical communications payload. It was launched in 2017. To improve the satellite’s attitude determination, which is used to point the payload, a new sensor fusion algorithm based on a low pass filter and a multiplicative extended Kalman filter (MEKF) was developed. As an operational satellite, improvements are only possible via software updates. The algorithm estimates the satellite's attitude from star tracker and fibre-optical gyroscope (FOG) measurements. It also estimates the gyroscope bias. The global attitude estimate uses a quaternion representation, while the Kalman filter uses Gibbs Parameters to calculate small attitude errors. Past Kalman filter predictions are saved for several time steps so that a delayed star tracker measurement can be used to update the prediction at the time of measurement. The estimate at the current time is then calculated by predicting the system attitude based on the updated past estimate. The prediction step relies on the low-pass-filtered gyroscope measurements corrected by the bias estimate. The new algorithm was developed as part of a master’s thesis at the University of Stuttgart, where Flying Laptop was developed and built. It was simulated in a MATLAB/Simulink environment using the European Space Agency’s GAFE framework. In addition, the new filter was applied to measurement data from the satellite. The results were used to compare the performance with the current filter implementation. The new Kalman filter can deal with delayed, missing, or irregular star tracker measurements. It features a lower computational complexity than the previous standard extended Kalman filter used on Flying Laptop. The mean error of the attitude estimate was reduced by up to 90%. The low pass filter improves the rotation rate estimate between star tracker measurements, especially for biased and noisy gyroscopes. However, this comes at the cost of potentially less accurate attitude estimates. Educational satellites benefit from the new algorithm given their typically limited processing power and cheap commercial-off-the-shelf (COTS) sensors. This paper presents the approach in detail and shows its benefits
Update on the status of the Educational Irish Research Satellite (EIRSAT-1)
Authors: Doyle Maeve , Murphy David , Reilly Jack , Thompson Joseph , Walsh Sarah , Akarapu Sai Krishna Reddy , Dunwoody Rachel , Erkal Jessica , Finneran Gabriel , Mangan Joseph , Marshall Fergal , Salmon Lána , Somers Eoghan , Franchi Loris , Ha Lily , Palma David , Ulyanov Alexey , Martin Carrillo Antonio , McBreen Sheila , McKeown David , O'Connor William , Wall Ronan , Hanlon Lorraine
Published: July 2022

The Educational Irish Research Satellite, EIRSAT-1, is a 2U CubeSat being implemented by a student-led team at University College Dublin, as part of the 2nd round of the European Space Agency’s Fly Your Satellite! programme. In development since 2017, the mission has several scientific, technological and outreach goals. It will fly an in-house developed antenna deployment module, along with three custom payloads, which are integrated with commercial off-the-shelf subsystems. In preparation for the flight model, a full-system engineering qualification model of the spacecraft has undergone an extensive period of test campaigns, including full functional tests, a mission test, and environmental testing at the European Space Agency’s CubeSat Support Facility in Redu, Belgium. Beyond the technical, educational, and capacity-building goals of the mission, EIRSAT-1 aims to inspire wider study of STEM subjects, while highlighting the importance of multidisciplinary teams and creating greater awareness of space in everyday life. A wide range of outreach activities are being undertaken to realise these aims. This paper provides a status update on key aspects of the EIRSAT-1 project and the next steps towards launch