scholarly journals Conceptual Design of Mars Lander with Novel Impact Intriguing System

2021 ◽  
Author(s):  
Malaya Kumar Biswal M ◽  
Ramesh Naidu Annavarapu
Keyword(s):  
Conceptual Design ◽  
Impact Force ◽  
Preliminary Results ◽  
The Past ◽  
System P ◽  
Planetary Landing ◽  
Ultimate Principle

Planetary landing is the ultimate principle of extraterrestrial exploration. But ef-fectuating successful landing is a strenuous assignment because lander may ex-perience a malfunction and can perform defective landing at any stage due to numerous factors. Here from the perspective of inefficient impact attenuator, we propose a design of Mars lander with a novel impact absorber fabricated from alloyed silicon-chromium spring damper integrated with a dual cylinder of distinct diameter to counteract the pressure variance exerted during landing. In addition to this, we have reviewed the past landing missions and discussed the approach to design and fabrication. Finally, from the derived formulations, we have displayed the preliminary results and we expect that the attenuator may bear an impact force of 20-140 kN for grounding 0.2-1.0-ton class crewed or cargo landers on Mars.

Granular bainite or granular ferrite? A preliminary TEM investigation of an HSLA-100 steel

1991 ◽  
Vol 49 ◽  
pp. 584-585
Author(s):  
R. Varughese ◽  
S. W. Thompson ◽  
P. R. Howell
Keyword(s):  
Room Temperature ◽  
Transformation Products ◽  
Accurate Description ◽  
Granular Bainite ◽  
Preliminary Results ◽  
The Past ◽  
Light Micrograph ◽  
Multiphase Reaction ◽  
Detailed Nature

Ever since Habraken and Economopoulos first employed the term granular bainite to classify certain unconventional transformation products in continuously cooled steels, the term has been widely accepted and used, despite the lack of a clear consensus as to the detailed nature of the transformation products which constitute granular bainite. This paper presents the preliminary results of a TEM investigation of an 0.04 wt% C, copper-containing steel (designated HSLA-100). It is suggested that the term granular ferrite rather than granular bainite is a more accurate description of this multiphase reaction product.Figure 1 is a light micrograph of a sample which had been air-cooled from 900°C to room temperature. The microstructure is typical of that which has been termed granular bainite in the past and appears to consist of equiaxed ferritic grains together with other minor transformation products. In order to examine these structures in more detail, both continuously cooled and isothermally transformed and quenched materials have been examined with TEM. Granular bainite has been found in virtually all samples.

Design Model Applied to the Design of Production Machines

1999 ◽  
Author(s):  
B. H. de Roode ◽  
H. A. Crone
Keyword(s):  
Computer Program ◽  
Conceptual Design ◽  
Specific Model ◽  
Computer Support ◽  
Design Model ◽  
Design Stage ◽  
Multiple Views ◽  
General Design ◽  
The Past ◽  
Design Activities

Abstract This paper describes a general design model that serves as a base for computer-support in the conceptual design stage. The model consists of a model of the artefact to be designed, design activities and knowledge. The artefact model contains multiple views, each highlighting a certain aspect of the design. Design activities are performed to create this model and knowledge describes information generated in the past that can be reused. The general design model has been used to develop a specific model for the design of production machines. This specific model has been implemented in a prototype computer-program and has been evaluated within several companies. The results are promising and show that designers gain new insights by using the model.

Cartilage Scales Embedded in Fibrin Gel

2017 ◽  
Vol 33 (02) ◽  
pp. 225-232 ◽  
Author(s):  
Milos Kovacevic ◽  
Frank Riedel ◽  
Jochen Wurm ◽  
Gregor Bran
Keyword(s):  
Regenerative Medicine ◽  
Surgical Techniques ◽  
Fibrin Gel ◽  
Platelet Rich Fibrin ◽  
Preliminary Results ◽  
Advantages And Disadvantages ◽  
The Past ◽  
Dorsal Nasal Augmentation ◽  
Diced Cartilage ◽  
Nasal Augmentation

Multiple techniques have been described for dorsal nasal augmentation in rhinoplasty. In this article, we review common surgical techniques for raising the dorsum or eliminating dorsal irregularities, by highlighting inherent advantages and disadvantages of each method. Within the past few years, the use of diced cartilage grafts has become the workhorse in this field of interest. To overcome drawbacks of methods based on diced cartilage, we present a new concept for autologous augmentation, using regenerative medicine protocols. A mix of cartilage scales with cartilage pâté was embedded in platelet-rich fibrin (PRF). Since December 2015, a total of 48 patients were treated with this technique. Based on our preliminary results, cartilage scales in PRF appear to be a promising and reliable alternative to existing procedures for dorsal nasal augmentation.

The verbal system

2019 ◽  
pp. 176-231
Author(s):  
D. Gary Miller
Keyword(s):  
The Other ◽  
Past Participle ◽  
Verbal System ◽  
The Third ◽  
The Past ◽  
Change Of State ◽  
System P ◽  
Third Person ◽  
The Third Person ◽  
Weak Verbs

Verbs in Gothic are thematic, athematic, or preterite present. Several classes, including modals, are discussed. Strong verbs have seven classes, weak verbs four. Inflectional categories are first, second, and third person, singular, dual (except in the third person), and plural number. Tenses are nonpast and past/preterite. There are two inflected moods, indicative and optative, and two voices (active, passive). The passive is synthetic in the nonpast indicative and optative. The past system features two periphrastic passives, one stative-eventive with wisan (be), the other inchoative and change of state with wairþan (become). Middle functions are mostly represented by simple reflexive structures and -nan verbs. Nonfinite categories include one voice-underspecified infinitive, a nonpast and past participle, and a present active imperative. The third person imperative is normally expressed by an optative.

scholarly journals Analyses of the LMC Novae

1999 ◽  
Vol 190 ◽  
pp. 391-392
Author(s):  
Karen M. Vanlandingham ◽  
Greg J. Schwarz ◽  
Sumner Starrfield ◽  
Peter H. Hauschildt ◽  
Steven N. Shore ◽  
...  
Keyword(s):  
Stellar Evolution ◽  
Large Magellanic Cloud ◽  
Optical Spectra ◽  
Classical Novae ◽  
Preliminary Results ◽  
Elemental Abundances ◽  
Ultraviolet Spectra ◽  
The Past ◽  
Consistent Manner ◽  
Ism Abundances

In the past 10 years, 6 classical novae have been observed in the Large Magellanic Cloud (LMC). We have begun a study of these objects using ultraviolet spectra obtained by IUE and optical spectra from nova surveys. We are using the results of this study to further our understanding of novae and stellar evolution.Our study includes analysis of both the early, optically thick spectra using model atmospheres (Hauschildt et al. 1992), and the later nebular spectra using optimization of photoionization codes (Ferland 1996; James & Roos 1993). By analysing all the LMC novae in a consistent manner, we can compare their individual results and use their combined properties to calibrate Galactic novae. In addition, our studies can be used to determine the elemental abundances of the nova ejecta, the amount of mass ejected, and the contribution of novae to the ISM abundances. To date we have analysed Nova LMC 1988#1 (Schwarz et al. 1998) and Nova LMC 1990#1 (Vanlandingham et al. 1999), and have obtained preliminary results for Nova LMC 1991. The results of this work are presented in this poster.

The Challenges of Electronic Cooling: Past, Current and Future

2004 ◽  
Vol 126 (4) ◽  
pp. 491-500 ◽  
Author(s):  
Richard C. Chu
Keyword(s):  
Conceptual Design ◽  
Electronics Cooling ◽  
Electronic Cooling ◽  
Sponsored Research ◽  
Distant Future ◽  
The Past ◽  
Engineering Development ◽  
Wide Range ◽  
Cooling Technology

This paper represents my personal recapitulation of my 4 decades of continuous involvement in all phases of electronic cooling, from conceptual design, through engineering development to product implementation. The cooling designs that we applied successfully in the past are reviewed chronologically. The challenges we are currently facing are also discussed and an attempt is made to forecast the challenges that will confront the electronics cooling community in the near and distant future. The paper includes a summary of IBM sponsored research spanning a period of 25 years at 12 universities on a wide range of topics related to electronic cooling technology.

Polarization

2019 ◽  
Author(s):  
Nolan McCarty
Keyword(s):  
American Politics ◽  
Social Economic ◽  
The United States ◽  
Political Climate ◽  
The Past ◽  
Political Conflicts ◽  
System P ◽  
2016 Election ◽  
State Of Affairs ◽  
Legislative Districts

The 2016 election of Donald J. Trump invoked a time for reflection about the state of American politics and its deep ideological, cultural, racial, regional, and economic divisions. But one aspect that the contemporary discussions often miss is that these fissures have been opening over several decades and are deeply rooted in the structure of American politics and society. Nolan McCarty's Polarization: What Everyone Needs to Know® is an accessible introduction to polarization in America. McCarty takes readers through what scholars know and don't know about the origins, development, and implications of our rising political conflicts, delving into social, economic, and geographic determinants of polarization in the United States. While the current political climate makes it clear that extreme views are becoming more popular, McCarty also argues that, contrary to popular belief, the 2016 election was a natural outgrowth of 40 years of polarized politics, instead of a significant break with the past. He explains the factors that have created this state of affairs, including gerrymandered legislative districts, partisan primary nomination systems, and our private campaign finance system. He also considers the potential of major reforms such as instating proportional representation or single-transferable voting to remedy extreme polarization. A concise overview of a complex and crucial topic in US politics, this book is for anyone wanting to understand how to repair the cracks in our system.

FIELD EVALUATION AND THE IMPORTANCE OF THE ASCOCHYTA COMPLEX ON PEAS

1965 ◽  
Vol 45 (1) ◽  
pp. 27-33 ◽  
Author(s):  
V. R. Wallen
Keyword(s):  
Seed Germination ◽  
Secondary Infection ◽  
Field Evaluation ◽  
Mycosphaerella Pinodes ◽  
Relative Importance ◽  
Seed Infection ◽  
Yield Losses ◽  
Preliminary Results ◽  
The Past ◽  
Ascochyta Pisi

Mycosphaerella pinodes Berk, and Blox. Vestgrn. and Ascochyta pinodella Jones were found to cause serious yield losses in the field. Although a higher percentage of seeds became infected with Ascochyta pisi Lib. than with either of the fungi referred to above, yield losses were considerably less, This finding is important in setting disease tolerances for various grades of seed since in the past arbitrary scales for these three organisms have been set without any knowledge of the relative importance of seed infection to field epidemiology. Only races III and IV of A. pisi caused significant losses in yield. Cycloheximide (100 p.p.m.) applied as a spray in the field significantly reduced seed infection by A. pisi but also reduced seed germination. Phygon 50W and griseofulvin 50W did not reduce germination but reduced seed infection considerably although not completely. Granted, preliminary results suggested that certain chemicals gave a selective control of the races of A. pisi, but this phenomenon could not be further demonstrated because of secondary infection in the field.

Bathymetry and acoustic facies beneath the former Larsen-A and Prince Gustav ice shelves, north-west Weddell Sea

2001 ◽  
Vol 13 (3) ◽  
pp. 312-322 ◽  
Author(s):  
Carol J. Pudsey ◽  
Jeffrey Evans ◽  
Eugene W. Domack ◽  
Peter Morris ◽  
Rodolfo A. Del Valle
Keyword(s):  
Continental Shelf ◽  
Weddell Sea ◽  
Shelf Edge ◽  
Ice Shelf ◽  
Ice Shelves ◽  
North West ◽  
Preliminary Results ◽  
The Past ◽  
Acoustic Facies ◽  
Marine Mud

We present preliminary results of the first detailied surveys of the former Larsen-A Ice Shelf, Larsen Inlet and southern Prince Gustav Channel, where disintegration of small ice shelves in the past ten years has exposed the seafloor. Glacial troughs in the Larsen-A area, Larsen Inlet and Prince Gustav Channel reach 900–1100 m depth and have hummocky floors. Farther south-east, the continental shelf is shallower (400–500 m) and its surface is fluted to smooth, with the density of iceberg furrowing increasing towards the shelf edge. Acoustic profiles show a drape of transparent sediment 4–8 m thick in Prince Gustav Channel, thinning southwards. In cores, this drape corresponds to diatom-bearing marine and glacial-marine mud. In the Larsen-A area and Larsen Inlet, acoustically opaque sediment includes proximal ice shelf glaciomarine gravelly and sandy muds, and firm to stiff diamicts probably deposited subglacilly. These are overlain by thin (up to 1.3 m) glaciomarine muds, locally with distinctive diatom ooze laminae.

The Growth of Government Expenditure

1984 ◽  
Vol 108 ◽  
pp. 34-41 ◽  
Author(s):  
M. S. Levitt
Keyword(s):  
United Kingdom ◽  
Government Spending ◽  
Public Expenditure ◽  
Government Expenditure ◽  
Public Spending ◽  
Green Paper ◽  
Preliminary Results ◽  
The Past ◽  
The United Kingdom ◽  
Future Policy

There is much debate at present about trends in public expenditure. The recent Green Paper on the longer-term outlook for public spending describes how public expenditure has risen faster than GDP in the past and raises the question whether total public spending need grow at all, in real terms, in future although the growth of GDP is projected at over 2 per cent a year. This article is not intended to offer any normative comment on future policy for government spending. Its purpose is to describe some preliminary results of a study of the growth of government spending and its relationship to GDP in the United Kingdom; it also makes some comparisons, in rather broad terms, of the experience of this country with that of some other countries.

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