Articles for "Digitales Höhenmodell"

to homepage
Aeronautics | 18. January 2022 | posted by Tim Stelkens-Kobsch

The SATIE project – greater security for airports

© whity
Credit: © whity
Airports are complex places, and that makes them vulnerable. In the SATIE project, leading EU partner organisations have joined forces to improve the resilience of European airports in the face of cyber and physical attacks.

As part of the Security of Air Transport Infrastructure of Europe (SATIE) project – a complex scenario at Zagreb Airport – one of the project partners demonstrated the potential effect of an extortion attack on an airport's Baggage Handling System (BHS). In the process, 'attackers' carried out virus attacks on the control system of the BHS live and on site. The airport staff were asked to detect and fend off these attacks during the demonstration. They were provided with the SATIE toolkit developed as part of the project. This recognises physical and cyber-attacks – or combinations of the two – and provides decision-making suggestions to clarify the situation.

The simulated attack on the BHS was just one of a total of five scenarios devised to test the new components of the SATIE toolkit as realistically as possible. Each scenario provides a step-by-step description of how a specific complex attack on an airport would be likely to proceed. read more

Space | 15. December 2021 | posted by Bed-rest-study

SANS-CM bed rest study: Detecting space eye disease while lying down

Messung der Veränderung der Augachsenlänge mittels objektive Refraktion zum Ausschluss einer Verkürzung des Augapfels
Credit: © DLR. All rights reserved
A large number of eye examinations await the test persons in the current bed rest study. The image shows the measurement of the change in eye axis length by means of the so-called objective refraction to exclude a shortening of the eyeball.

Living in space puts an enormous strain on the body. Among other things, astronauts are exposed to space radiation and experience their muscles deteriorate and body fluids shift towards the head. To protect against the radiation, international research is being conducted on protective vests, for example in the MARE mission. Effective training programmes have been developed to combat muscle atrophy, so that today astronauts hardly have any difficulties upon returning to Earth, even after spending months on the International Space Station (ISS). However, the increased pressure in the head due to the changed fluid distribution can lead to permanent problems – especially for the eyes. Time and again, space travellers report a deterioration of their eyesight, with about 70 percent experiencing eye changes, either temporarily during the stay in space or permanently.

The causes are still unclear. There are some theories but no evidence explaining why this affects some astronauts and not others, but it is clear that the eye condition is a significant risk. If we think about the future of human spaceflight with missions to the Moon and Mars, stays in weightlessness will last longer and longer. Through all of this, the health and safety of the space travellers must be maintained. Therefore, reliable prevention and countermeasures are needed. read more

Space | 08. December 2021 | posted by Bed-rest-study

SANS-CM bed rest study: Docking manoeuvres while lying down, guitar concerts and jelly legs

Probandin der SANS-CM-Bettruhestudie in der Unterdruckkammer LBNP
Credit: © DLR. All rights reserved
Six test participants spent two times three hours per day in the low pressure chamber during the bed-rest phase. They were built by DLR in coordination with NASA and they ensure that the body fluids are 'pulled' to the lower half of the body.
 

The first campaign of the SANS-CM bed rest study has come to an end and the DLR Institute of Aerospace Medicine is already preparing for the next one, which will begin in spring 2022. While the test participants spent their last days after their 30-day bed rest at :envihab, the research team has been working on processing the extensive data and continuing the study with new test participants. Before this round's participants packed their bags at the end of November to resume their real lives, we asked them about their experiences. read more

Space | 01. December 2021 | posted by Bed-rest-study

SANS-CM bed rest study: Subject D1 looks back on his 30 days in bed

medizinische Untersuchungen während der Bettruhestudie SANS-CM am DLR Köln
Credit: © DLR. All rights reserved
The daily schedule for the bed rest study includes a number of medical examinations, including intraocular pressure measurement (Fig.1), an MRI (2), an assessment of heartrate and stroke volume via inert gas rebreathing (3) and ultrasound measurements (4)

I 'm at the entrance to the DLR premises in Cologne. Somehow everything seems a bit surreal. The door of the :envihab is about to close behind me for eight weeks. I feel this strange sensation come over me, coupled with keen curiosity and tension. Although it has taken a long time for the study to get started, it's as though someone has only just asked me if I fancy taking part. And now the moment has arrived: as of today, I am Subject D1 in the new bed rest study at DLR.

I'm 42 years old and in my 'normal life' I work as a senior electrician in Facility Management at a hospital specialising in cardiovascular diseases. I'm mainly responsible for building control technology and the power supply. When you have an interest in technical things like I do, it generally comes with a keen sense of curiosity. That's why I'm prepared to lie down for 30 days. read more

Space | 25. November 2021 | posted by Bed-rest-study

The SANS-CM bed rest study: Lying down for 30 days for space research

DLR-Unterdruckzylinder LBNP (Lower Body Negative Pressure Device)
Credit: DLR (CC-BY 3.0)
The beds in the current bed rest study at DLR. As usual, the head end is tilted six degrees below the horizontal. The vacuum cylinders that enclose the body from the waist down are a new feature; they are used on the test participants for six hours a day.

What happens to humans in microgravity conditions? How do space conditions affect the human body? How can we prevent adverse effects on long-term spaceflight? Scientists on Earth are also asking themselves these kinds of questions. And they're coming up with answers, despite the occurrence of gravity. The researchers can outsmart it, as the ongoing bed rest study at :envihab, our aerospace medicine research facility, demonstrates. Here, eight men and four women lie in bed for 30 days straight. The head end of each bed is tilted six degrees downwards and there is no pillow. In these conditions, body fluids are distributed as they would be in microgravity, flowing from the legs towards the head. The test participants are 'astronauts on Earth'. read more

Space | 08. October 2021 | posted by Nicole Schmitz

Perseverance – the name says it all

Credit: NASA/JPL-Caltech/MSSS
Perseverance takes a selfie after successful acquisition of a sample

On 18 February 2021, the Perseverance rover of NASA's Mars 2020 mission landed on Mars safe and sound. The research mission, initially scheduled to last two years, has begun. In this blog, DLR researcher Nicole Schmitz, together with her colleague Frank Preusker, will report regularly on the progress of the mission and the camera experiment in which they are involved. Both are part of the Science Team of the Mastcam-Z instrument, a stereo camera located on Perseverance's approximately two-metre-high mast. read more

Space | 21. September 2021 | posted by Celia Baumhoer

Aerial campaign on the Aletsch Glacier

DLR-Wissenschaftler auf dem Weg über den Gletscher zur Konkordiahütte
Copyright: © DLR/Celia Baumhoer
The path across the glacier to the Konkordia Hut

Only superlatives can properly describe the sheer magnitude of the Aletsch Glacier. Measuring over 22 kilometres in length and with a thickness of up to 900 metres, it is the largest glacier in the Alps, accounting for one fifth of Switzerland's total ice mass. But climate change is obviously leaving its mark on the Aletsch Glacier as well. How has the snow cover changed in the Jungfrau-Aletsch region over recent decades? How much mass is the glacier losing each year? At the start of September 2021, a DLR team from the Polar Monitor Project embarked on a two-week mission to seek answers to these and other questions using high-resolution aerial images and a variety of satellite sensors. read more

Aeronautics | 01. September 2021 | posted by Bernd Kärcher

Soot in aircraft exhaust and the climate impact of air traffic

Kondensstreifen am Himmel
Credit:DLR (CC BY-NC-ND 3.0)
Aircraft engines emit soot particles that act as 'condensation nuclei'. Small cold water droplets immediately condense and freeze into minute ice crystals, becoming visible as contrails in the sky.

Aircraft emissions are associated with all sorts of environmental problems. Researchers have long been studying the different kinds of emissions in order to understand how air transport is altering the composition of the atmosphere, cloud cover and the climate. Aircraft contrails are anthropogenic clouds of ice. My work in the 1990s showed that the physical properties of the white wispy trails aircraft trace across the sky are best explained by their soot emissions – black carbon particles and condensable substances like sulphuric acid produced during the combustion of fossil fuels such as kerosene. read more

Aeronautics | 08. June 2021 | posted by Florian Wozny

Climate-neutral flight through carbon dioxide offsets – an interim solution

Flugzeug am Himmel
Credit: DLR/Alejandro Morellon (CC-BY 3.0)
More environmentally friendly air transport of the future – interim goal of climate-neutral flight

Since 2021, airlines have had to offset emissions on international flights that exceed the average values for 2019. This is done with the help of carbon dioxide compensation projects that invest in renewable energy sources or the preservation of forests, for example – that is, reduce or store greenhouse gas emissions. Credits are then issued for these projects. However, the climate impact of the credits depends strongly on the underlying project types. In a new DLR discussion paper, my team and I show the limits of mandatory offsetting.

Rising fuel prices have already led to airlines investing in technological advancements, as fuel accounts for approximately one third of total operating costs. For example, engines and combustion processes have been improved over the years. Fuel consumption is falling by about two percent per year. However, the environmental benefits have been offset by the enormous increase in air traffic. Policy-makers are faced with a dilemma. read more

Space | 22. March 2021 | posted by Manfred Gottwald

Using principles from painting – creating 3D-effect satellite images in true colour

Die physische Karte des Nördlinger Ries, abgeleitet aus einem farbkodierten, schräg beleuchteten digitalen Höhenmodell von TanDEM-X
Credit: © DLR
A physical map of the Nördlinger Ries, derived from a colour-coded, diagonally illuminated digital elevation model created using data acquired by TanDEM-X

How can an impression of three-dimensionality be created using a two-dimensional medium? In art, this question arose centuries ago. Certain painting techniques have since evolved to simulate effects of light and shadow, creating a 3D effect for the viewer. Such effects are referred to as trompe-l'œil – they 'deceive the eye'.

Earth observation satellites with multispectral sensors provide images in natural colours when their red, green and blue (RGB) channels are combined. However, they tend to appear somewhat 'flat'. To turn them into attractive, three-dimensional representations, they must first be 'transformed' into three dimensions. This can be achieved if we use proven methods from art as a guide in science, but this requires elevation information. read more