scholarly journals Mass spectrometry of planetary exospheres at high relative velocity: direct comparison of open- and closed-source measurements

2017 ◽  
Vol 6 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Stefan Meyer ◽  
Marek Tulej ◽  
Peter Wurz
Keyword(s):  
Open Source ◽  
Noble Gases ◽  
Mass Range ◽  
Ion Source ◽  
Thermal Mode ◽  
Icy Moons ◽  
Neutral Gas ◽  
Major Interest ◽  
Potential Habitats ◽  
Closed Source

Abstract. The exploration of habitable environments on or inside icy moons around the gas giants in the solar system is of major interest in upcoming planetary missions. Exactly this theme is addressed by the JUpiter ICy moons Explorer (JUICE) mission of ESA, which will characterise Ganymede, Europa and Callisto as planetary objects and potential habitats. We developed a prototype of the Neutral Gas and Ion Mass spectrometer (NIM) of the Particle Environment Package (PEP) for the JUICE mission intended for composition measurements of neutral gas and thermal plasma. NIM/PEP will be used to measure the chemical composition of the exospheres of the icy Jovian moons. Besides direct ion measurement, the NIM instrument is able to measure the inflowing neutral gas in two different modes: in neutral mode, where the gas enters directly the ion source (open source), and in thermal mode, where the gas gets thermally accommodated to the wall temperature by several collisions inside an equilibrium sphere, called antechamber, before entering the ion source (closed source). We performed measurements with the prototype NIM using a neutral gas beam of 1 up to 4.5 km s−1 velocity in the neutral and thermal mode. The current trajectory of JUICE foresees a flyby velocity of 4 km s−1 at Europa; other flybys are in the range of 1 up to 7 km s−1 and orbital velocity in Ganymede orbits is around 2 km s−1. Different species are used for the gas beam, such as noble gases Ne, Ar, Kr as well as molecules like H2, methane, ethane, propane and more complex ones. The NIM prototype was successfully tested under realistic JUICE mission conditions. In addition, we find that the antechamber (closed source) behaves as expected with predictable density enhancement over the specified mass range and within the JUICE mission phase velocities. Furthermore, with the open source and the closed source we measure almost the same composition for noble gases, as well as for molecules, indicating no additional fragmentation of the species recorded with the antechamber for the investigated parameter range.

scholarly journals Mass spectrometry of planetary exospheres at high relative velocity: direct comparison of open- and closed source measurements

2016 ◽  
Author(s):  
Stefan Meyer ◽  
Marek Tulej ◽  
Peter Wurz
Keyword(s):  
Open Source ◽  
Noble Gases ◽  
Mass Range ◽  
Ion Source ◽  
Thermal Mode ◽  
Icy Moons ◽  
Neutral Gas ◽  
Major Interest ◽  
Potential Habitats ◽  
Closed Source

Abstract. The exploration of habitable worlds inside icy moons around the gas giants in the Solar System is of major interest in upcoming planetary missions. Exactly this theme is addressed by the Jupiter Icy Moons Explorer (JUICE) mission of ESA, which will characterise Ganymede, Europa and Callisto as planetary objects and potential habitats. We developed a prototype of the Neutral gas and Ion Mass spectrometer (NIM) of the Particle Environment Package (PEP) for the JUICE mission intended for composition measurements of neutral gas and thermal plasma. NIM/PEP will be used to measure the chemical composition of the exospheres of the icy Jovian moons. Besides direct ion measurement, the NIM instrument is able to measure the inflowing neutral gas in two different modes: in neutral mode the gas enters directly the ion source (open source) and in thermal mode where the gas gets thermally accommodated to the wall temperature by several collisions inside an equilibrium sphere, called antechamber, before entering the ion-source (closed source). We performed measurements with the prototype NIM using a neutral gas beam of 1 up to 4.5 km s−1 velocity in the neutral and thermal mode. The current trajectory of JUICE foresees a flyby velocity of 4 km s−1 at Europa, other flybys are in the range of 1 up to 7 km s−1 and orbital velocity in Ganymede orbits is around 2 km s−1. Different species are used for the gas beam, such as noble gases Ne, Ar, Kr as well as molecules like H2, methane, ethane, propane and more complex ones. The NIM prototype was successfully tested under realistic JUICE mission conditions. In addition, we find that the antechamber (closed source) behaves as expected with predictable density enhancement over the specified mass range and within the JUICE mission phase velocities. Furthermore, with the open source and the closed source we measure almost the same composition for noble gases, as well as for molecules, indicating no additional fragmentation of the species recorded with the antechamber for the investigated parameter range.

Development of the NIM Mass spectrometer for Exploration of Jupiter’s Icy Moons Exospheres

2020 ◽  
Author(s):  
Martina Föhn ◽  
Marek Tulej ◽  
André Galli ◽  
Audrey Helena Vorburger ◽  
Davide Lasi ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Surface Composition ◽  
Ion Source ◽  
High Mass ◽  
Performance Tests ◽  
Icy Moons ◽  
Neutral Particles ◽  
Set Constraints ◽  
Neutral Gas ◽  
Closed Source

<p>Investigation of habitable environments is one of the main objectives in upcoming space missions. The JUICE mission will investigate Jupiter’s environment in the solar system and its icy moons Ganymede, Callisto and Europa as examples for potentially habitable worlds around a gas giant. The Particle Environment Package (PEP) on the JUICE satellite will investigate Jupiter’s icy moons and their environment. As part of PEP, the Neutral gas and Ion Mass spectrometer (NIM) will measure the chemical composition of the exospheres of the icy moons. These measurements give information about the surface composition of the moons and will set constraints on their formation processes.</p><p>NIM is a Time of Flight mass spectrometer with two entrances for neutral particles and ions. The gas enters the instrument from spacecraft ram direction. With the open source neutral particles and ions enter the ionisation region directly. With the closed source neutral particles get thermalized using an antechamber before entering the ion source. Particles entering with higher velocity are therefore easier to detect through the antechamber.</p><p>Initial performance tests with the NIM Protoflight Model (PFM) were done. The storage capability of the ion source was tested, the functionality of the antechamber was verified and we measured masses up to 642 u to demonstrate the high-mass performance of NIM. Furthermore, different subunits of the NIM instrument were successfully tested, such as the redesigned ion source and flight electronics connected with the NIM sensor head.</p>

Initial Calibration Results of the NIM Flight Spare Mass spectrometer for Exploration of Jupiter’s Icy Moons Exospheres

2021 ◽  
Author(s):  
Martina Föhn ◽  
Marek Tulej ◽  
André Galli ◽  
Audrey Helena Vorburger ◽  
Davide Lasi ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Surface Composition ◽  
European Space Agency ◽  
Ion Source ◽  
Icy Moons ◽  
Neutral Particles ◽  
Neutral Gas ◽  
High Speeds ◽  
Space Agency ◽  
Ionization Region

<p>The search for life is one of the key topics in modern space science. The JUICE mission of the European Space Agency ESA will investigate Jupiter and its icy moons Ganymede, Callisto and Europa, with Europa being an example of a potentially habitable world around a giant gas planet. The Particle and Environment Package, PEP, on board of the JUICE spacecraft will investigate Jupiter’s icy moons and their environment. The Neutral gas and Ion Mass spectrometer NIM will investigate the icy moon’s exospheres to investigate their formation and the interaction processes of the exospheres with the moons’ surface and Jupiter’s strong magnetic field. It will enhance our understanding of the processes involved in the interactions of ion bombardment on the icy moons' surfaces. From these measurements, we will derive the moons’ surface composition and their formation processes.</p><p>NIM is a time-of-flight mass spectrometer with two particle entrances: an open-source entrance to measure neutral particles and ions directly and a close source entrance where neutral particles get thermalized before entering the sensor’s ionization region. This allows detecting of particles with high speeds. NIM has a specially designed ion storage source and an ion-mirror to double the flight distance of the produced ions by keeping the sensor at a minimal size.</p><p>In this contribution, we show calibration results of the NIM flight spare instrument on one hand operated with laboratory and on the other operated with flight electronics. We demonstrate the performance of NIMs ion-source, verify the performance of the closed-source antechamber. NIM has a demonstrated mass resolution of m/Δm 800.</p>

Converting Raw Accelerometer Data to Activity Counts Using Open-Source Code: Implementing a MATLAB Code in Python and R, and Comparing the Results to ActiLife

2021 ◽  
pp. 1-7
Author(s):  
Ruben Brondeel ◽  
Yan Kestens ◽  
Javad Rahimipour Anaraki ◽  
Kevin Stanley ◽  
Benoit Thierry ◽  
...  
Keyword(s):  
Open Source ◽  
Pearson Correlation ◽  
Vertical Axis ◽  
Accelerometer Data ◽  
Accelerometer Sensor ◽  
Interclass Correlation ◽  
Acceleration Data ◽  
The Right ◽  
Pearson Correlations ◽  
Closed Source

Background: Closed-source software for processing and analyzing accelerometer data provides little to no information about the algorithms used to transform acceleration data into physical activity indicators. Recently, an algorithm was developed in MATLAB that replicates the frequently used proprietary ActiLife activity counts. The aim of this software profile was (a) to translate the MATLAB algorithm into R and Python and (b) to test the accuracy of the algorithm on free-living data. Methods: As part of the INTErventions, Research, and Action in Cities Team, data were collected from 86 participants in Victoria (Canada). The participants were asked to wear an integrated global positioning system and accelerometer sensor (SenseDoc) for 10 days on the right hip. Raw accelerometer data were processed in ActiLife, MATLAB, R, and Python and compared using Pearson correlation, interclass correlation, and visual inspection. Results: Data were collected for a combined 749 valid days (>10 hr wear time). MATLAB, Python, and R counts per minute on the vertical axis had Pearson correlations with the ActiLife counts per minute of .998, .998, and .999, respectively. All three algorithms overestimated ActiLife counts per minute, some by up to 2.8%. Conclusions: A MATLAB algorithm for deriving ActiLife counts was implemented in R and Python. The different implementations provide similar results to ActiLife counts produced in the closed source software and can, for all practical purposes, be used interchangeably. This opens up possibilities to comparing studies using similar accelerometers from different suppliers, and to using free, open-source software.

Dynamical Simulation Models of the Open Source Development Process

2008 ◽  
pp. 698-721
Author(s):  
I. P. Antoniades ◽  
I. Samoladas ◽  
I. Stamelos ◽  
L. Angelis
Keyword(s):  
Open Source ◽  
General Framework ◽  
Development Process ◽  
Simulation Models ◽  
Real Data ◽  
Simulation Methods ◽  
Dynamical Simulation ◽  
Closed Source ◽  
Free Open Source ◽  
Open Source Development

This chapter will discuss attempts to produce formal mathematical models for dynamical simulation of the development process of Free/Open Source Software (F/OSS) projects. First, a brief overview for simulation methods of closed source software development is given. Then, based on empirical facts reported in F/OSS case studies, we describe a general framework for F/OSS dynamical simulation models and discuss its similarities and differences to closed source software simulation. A specific F/OSS simulation model is introduced. The model is applied to the Apache project and to the gtk+ module of the GNOME project, and simulation outputs are compared to real data. The potential of formal F/OSS simulation models to turn into practical tools used by F/OSS coordinators to predict key project factors is demonstrated. Finally, issues for further research and efforts for improvement of this first-attempt model are discussed.

Effort, Time, and Staffing in Continually Evolving Open-Source Projects

2015 ◽  
pp. 1722-1743
Author(s):  
Liguo Yu
Keyword(s):  
Software Development ◽  
Open Source ◽  
Power Law ◽  
Development Time ◽  
Development Effort ◽  
Linux Kernel ◽  
Software Projects ◽  
Management And Development ◽  
Software Development Effort ◽  
Closed Source

Scheduling and staffing are important management activities in software projects. In closed-source software development, the relationships among development effort, time, and staffing have been well established and validated: the development effort determines the development time and the best number of developers that should be allocated to the project. However, there has been no similar research reported in open-source projects. In this chapter, the authors study the development effort, development time, and staffing in an open-source project, the Linux kernel project. Specifically, they investigate the power law relations among development effort, development time, and the number of active developers in the Linux kernel project. The authors find the power law relations differ from one branch to another branch in the Linux kernel project, which suggests different kinds of management and development styles might exist in different branches of the Linux kernel project. The empirical knowledge of software development effort obtained in this study could help project management and cost control in both open-source communities and closed-source industries.

scholarly journals Characterization of a cold cathode Penning ion source for the implantation of noble gases beneath 2D monolayers on metals: Ions and neutrals

2016 ◽  
Vol 34 (2) ◽  
pp. 020602 ◽  
Author(s):  
Huanyao Cun ◽  
Annina Spescha ◽  
Adrian Schuler ◽  
Matthias Hengsberger ◽  
Jürg Osterwalder ◽  
...  
Keyword(s):  
Noble Gases ◽  
Ion Source ◽  
Cold Cathode

scholarly journals Open Source Paradigm: A Synopsis of The Cathedral and the Bazaar for Health and Social Care

2016 ◽  
Vol 23 (2) ◽  
pp. 488
Author(s):  
Tim Benson
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Social Care ◽  
Source Code ◽  
Comprehensive Description ◽  
The Third ◽  
It Impacts ◽  
Health And Social Care ◽  
Software Engineers ◽  
Closed Source

Background: Open source software (OSS) is becoming more fashionable in health and social care, although the ideas are not new. However progress has been slower than many had expected.Objective: The purpose is to summarise the Free/Libre Open Source Software (FLOSS) paradigm in terms of what it is, how it impacts users and software engineers and how it can work as a business model in health and social care sectors.Method: Much of this paper is a synopsis of Eric Raymond’s seminal book The Cathedral and the Bazaar, which was the first comprehensive description of the open source ecosystem, set out in three long essays. Direct quotes from the book are used liberally, without reference to specific passages. The first part contrasts open and closed source approaches to software development and support. The second part describes the culture and practices of the open source movement. The third part considers business models.Conclusion: A key benefit of open source is that users can access and collaborate on improving the software if they wish. Closed source code may be regarded as a strategic business risk that that may be unacceptable if there is an open source alternative. The sharing culture of the open source movement fits well with that of health and social care.

A Comparative Analysis of Open Source Network Monitoring Tools

2016 ◽  
Vol 7 (2) ◽  
pp. 1-19
Author(s):  
Ali Al Shidhani ◽  
Khalil Al Maawali ◽  
Dawood Al Abri ◽  
Hadj Bourdoucen
Keyword(s):  
Open Source ◽  
Continuous Monitoring ◽  
Network Monitoring ◽  
Suitable Candidate ◽  
Monitoring Tools ◽  
Comparison Results ◽  
Increasing Demand ◽  
Closed Source ◽  
Network Administrators ◽  
Free Open Source

Nowadays, the heavy reliance on computer networks necessitates minimizing outage time, increasing the availability of services, and preventing network related problems. Such realization requires continuous monitoring and observation. This is not a trivial task. Thus, automatic network monitoring tools are deployed to monitor and analyze the traffic trespassing network devices. There is an increasing demand for automated network monitoring tools and selecting a suitable candidate can become a challenging task. Some computerized network monitoring tools and systems are available, including expensive proprietary/closed-source solutions and Free Open Source Software (FOSS) systems. Three of the most popular FOSS network monitoring systems are: Nagios, OpenNMS and Zabbix. They are solid competitors to the available proprietary solutions. This paper evaluates the strengths and weaknesses of these tools. A qualitative and quantitative evaluation of the tools were conducted through monitoring real-time network traffic. The paper presents a thorough comparison between the tools. The comparison results are vital for network administrators wishing to adopt the studied monitoring tools.

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