Long duration flights in Venus’ atmosphere using passive solar hot air balloons

In 1783, the Montgolfier brothers ushered in a new era of transportation and exploration when they used hot air to drive an un-tethered balloon to an altitude of ~2 km. Made of sackcloth and held together with cords, this balloon challenged the way we thought about human travel, and it has since evolved into a robust platform for performing novel science and testing new technologies. Today, high-altitude balloons regularly reach altitudes of 40 km, and they can support payloads that weigh more than 3000 kg. Long-duration balloons can currently support mission durations lasting ~55 days, and developing balloon technologies (i.e. Super-Pressure Balloons) are expected to extend that duration to 100 days or longer; competing with satellite payloads. This relatively inexpensive platform supports a broad range of science payloads, spanning multiple disciplines (astrophysics, heliophysics, planetary and earth science). Applications extending beyond traditional science include testing new technologies for eventual space-based application and stratospheric airships for planetary applications.

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Improved Passive Solar Hot-Air Heating of Residential Design and Research

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.88 ◽

2012 ◽

Vol 178-181 ◽

pp. 88-91

Author(s):

Bin Yang ◽

Shu Guang Jiang

Keyword(s):

Architectural Design ◽

Heating System ◽

Pilot Project ◽

Residential Design ◽

Planning And Design ◽

Hot Air ◽

Solar Fraction ◽

South Wall ◽

Design Requirements ◽

Passive Solar

Climate characteristics of Shihezi area, present passive solar building planning and design of residential and architectural design requirements; Through the improvement of traditional passive solar heating system, and adopt collection hot wall completely cover housing south wall and other measures to improve thermal efficiency sets. To pilot project as an example, the use of SLR method calculated, the system, in Shihezi the coldest month is January, solar fraction can reach 31%.

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Development of a Compact Solar Vegetable Dehydrator

10.21467/proceedings.118.21 ◽

2021 ◽

Author(s):

S. V Jadhav ◽

S. S Wangikar ◽

A. M Kulkarni ◽

M. K Patil ◽

A. A Bansode ◽

...

Keyword(s):

Solar Energy ◽

Moisture Content ◽

Shelf Life ◽

Flow Velocity ◽

Solar Collector ◽

Agricultural Products ◽

Hot Air ◽

Different Temperatures ◽

Passive Solar ◽

Time Required

Agricultural products, such as, vegetables are generally perishable and are difficult to store. Drying is one method to reduce the increase their shelf life. Dehydrators use different type of energy as per availability and requirement. Solar dehydrators are more popular since they use renewable solar energy. In this paper such a domestic passive solar dehydrator is designed and analysed for its utility and effectiveness. The dehydrator is designed for converting the perishable agricultural products into powders so that it can be stored and used for longer time. It is designed in two parts. The first part work as a solar energy collector and the second part works as the dehydrator. The heat from solar radiations is imparted to the air in the solar collector. This hot air is used in dehydrator foe drying agricultural products. The experimentation has been performed for different temperatures and flow velocity of air varying for different vegetables depending on their moisture content and time required to remove the moisture. It is observed that drying at different temperature is required for different vegetables to convert them into powder. The taste and colour of the powder produced are found to be good. Therefore, it is suitable and affordable even for farmers with lesser quantity of products.

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The LDE-Type Flare Occurrence (1969-1993)

International Astronomical Union Colloquium ◽

10.1017/s0252921100025458 ◽

1994 ◽

Vol 144 ◽

pp. 279-282

Author(s):

A. Antalová

Keyword(s):

Time Series ◽

Fourier Analysis ◽

Sunspot Cycle ◽

List Type ◽

Type Number ◽

Solar Cycles ◽

Type Iv ◽

Long Duration ◽

Cycle Maximum ◽

Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

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Transvenous catheter cardioversion with long duration rounded waveforms-initial findings

Journal of Cardiothoracic and Vascular Anesthesia ◽

10.1016/s1053-0770(98)90283-x ◽

1998 ◽

Vol 31 ◽

pp. 45

Author(s):

M HARBINSON

Keyword(s):

Long Duration

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Relation Between Level of Prefrontal Activity and Subject's Performance

Journal of Psychophysiology ◽

10.1027//0269-8803.13.2.117 ◽

1999 ◽

Vol 13 (2) ◽

pp. 117-125 ◽

Cited By ~ 14

Author(s):

Laurence Casini ◽

Françoise Macar ◽

Marie-Hélène Giard

Keyword(s):

Brain Activity ◽

Sensory Information ◽

Practice Phase ◽

Trained Subjects ◽

Anagram Task ◽

Economic Information ◽

Long Duration ◽

Level Of Activity ◽

The Brain ◽

Processing Mechanism

Abstract The experiment reported here was aimed at determining whether the level of brain activity can be related to performance in trained subjects. Two tasks were compared: a temporal and a linguistic task. An array of four letters appeared on a screen. In the temporal task, subjects had to decide whether the letters remained on the screen for a short or a long duration as learned in a practice phase. In the linguistic task, they had to determine whether the four letters could form a word or not (anagram task). These tasks allowed us to compare the level of brain activity obtained in correct and incorrect responses. The current density measures recorded over prefrontal areas showed a relationship between the performance and the level of activity in the temporal task only. The level of activity obtained with correct responses was lower than that obtained with incorrect responses. This suggests that a good temporal performance could be the result of an efficacious, but economic, information-processing mechanism in the brain. In addition, the absence of this relation in the anagram task results in the question of whether this relation is specific to the processing of sensory information only.

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Effects of Fatigue on Cognitive Performance in Long-Duration Simulated Flight Missions

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000191 ◽

2020 ◽

Vol 10 (2) ◽

pp. 82-93

Author(s):

Eduardo Rosa ◽

Ola Eiken ◽

Mikael Grönkvist ◽

Roger Kölegård ◽

Nicklas Dahlström ◽

...

Keyword(s):

Executive Functions ◽

Task Performance ◽

Cognitive Performance ◽

Cognitive Tasks ◽

Fatigue Index ◽

Fighter Aircraft ◽

Long Duration ◽

Metacognitive Accuracy

Abstract. Fighter pilots may be exposed to extended flight missions. Consequently, there is increasing concern about fatigue. We investigated the effects of fatigue and cognitive performance in a simulated 11-hr mission in the 39 Gripen fighter aircraft. Five cognitive tasks were used to assess cognitive performance. Fatigue was measured with the Samn–Perelli Fatigue Index. Results showed that performance in the non-executive task degraded after approximately 7 hr. Fatigue ratings showed a matching trend to the performance in this task. Performance in tasks taxing executive functions did not decline. We interpreted that fatigue can be overridden by increased attentional effort for executive tasks but not for non-executive components of cognition. Participants underestimated their performance and metacognitive accuracy was not influenced by fatigue.

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