The Application of Dynamic Programming to the Design of Invariant Auto-Stabilisers

1966 ◽  
Vol 70 (664) ◽  
pp. 469-476 ◽  
Author(s):  
P. Dyer ◽  
A. R. M. Noton ◽  
D. Rutherford

SummaryIn the past decade considerable attention has been given to the possibility of using self-adaptive control systems to cope with the problem of providing stability augmentation to aircraft over extended flight envelopes. On the other hand, it has sometimes been considered that insufficient attention has been given to the design of autostabilisers with fixed parameters. The authors have applied recent developments In dynamic programming to the design of aircraft autostabilisers. The methods provide a highly systematic approach to the design of multi-loop systems which is especially useful for control of the lateral mode. Furthermore, the resulting optimum multiple feedback coefficients vary little throughout the flight envelope and the use of fixed parameters for the whole of the flight envelope appears to be possible. Aerodynamic data for two aircraft were used: a supersonic VTOL aircraft and a supersonic transport.

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2806
Author(s):  
Muhammad Harris ◽  
Johan Potgieter ◽  
Kashif Ishfaq ◽  
Muhammad Shahzad

The collagen hydrolysate, a proteinic biopeptide, is used for various key functionalities in humans and animals. Numerous reviews explained either individually or a few of following aspects: types, processes, properties, and applications. In the recent developments, various biological, biochemical, and biomedical functionalities are achieved in five aspects: process, type, species, disease, receptors. The receptors are rarely addressed in the past which are an essential stimulus to activate various biomedical and biological activities in the metabolic system of humans and animals. Furthermore, a systematic segregation of the recent developments regarding the five main aspects is not yet reported. This review presents various biological, biochemical, and biomedical functionalities achieved for each of the beforementioned five aspects using a systematic approach. The review proposes a novel three-level hierarchy that aims to associate a specific functionality to a particular aspect and its subcategory. The hierarchy also highlights various key research novelties in a categorical manner that will contribute to future research.


1988 ◽  
Vol 27 (1) ◽  
pp. 81-83
Author(s):  
Nadeem A. Burney

Its been long recognized that various economies of the world are interlinked through international trade. The experience of the past several years, however, has demonstrated that this economic interdependence is far greater than was previously realized. In this context, the importance of international economic theory as an area distinct from general economics hardly needs any mentioning. What gives international economic theory this distinction is international markets for some goods and effects of national sovereignty on the character of economic activity. Wilfred Ethier's book, which incorporates recent developments in the field, is an excellent addition to textbooks on international economics for one- or twosemester undergraduate courses. The book mostly covers standard topics. A distinguishing feature of this book is its detailed analysis of the flexible exchange rates and a discussion of the various approaches used for their determination. Within each chapter, the author has extensively used facts, figures and major events to clarify the concepts in the light of the theoretical framework. The book also discusses, in a fair amount of detail, the existing international monetary system and the role of various international organizations.


2019 ◽  
pp. 451-458
Author(s):  
Peter W. Rein

Developments in the technology of production of sugar from sugarcane tend to be incremental improvements in an effort to reduce costs and boost revenue. Nonetheless the developments are significant and contribute to sustainable sugarcane enterprises. Some technologies have adapted to changing environmental conditions, and more attention is being given to boosting revenue through associated activities, particularly in enhancing the potential for sugarcane operations to exploit the energy value of sugarcane. This paper outlines recent developments of interest in processing sugarcane.


2017 ◽  
Vol 40 (3) ◽  
pp. 295-310
Author(s):  
Sabine Wilke

Every late spring since 1951, the Wiener Festwochen bring performers from around the world to Vienna for an opportunity to share recent developments in performance styles and present them to a Viennese public that seems to be increasingly open to experimentation. These festival weeks solidify a specific form of Viennese self-understanding and self-representation as a culture that is rooted in performance. This essay seeks to link two recent Austrian performances—one of them was part of the Wiener Festwochen in 2016, the other was staged in downtown Linz during the past few years—to this Austrian and specifically Viennese culture of performance by reading them as contemporary articulations of a tradition of radical performance art that can be traced back to the Viennese Actionism of the sixties and later feminist articulations in the seventies and eighties. They play on the dramatic effect of these actions, specifically their joy in cruelty, chaos, and orgiastic intoxication, by staging regressions and thus making visible what has been dammed up and repressed in contemporary society.1 Just as their historical models, these two performances merge the performing and the fine arts and they highlight provocative, controversial, and, at times, violent content. But they do it in an interspecies context that adds an entire layer of complexity to the project of societal and cultural critique.


2019 ◽  
Vol 26 (13) ◽  
pp. 2330-2355 ◽  
Author(s):  
Anutthaman Parthasarathy ◽  
Sasikala K. Anandamma ◽  
Karunakaran A. Kalesh

Peptide therapeutics has made tremendous progress in the past decade. Many of the inherent weaknesses of peptides which hampered their development as therapeutics are now more or less effectively tackled with recent scientific and technological advancements in integrated drug discovery settings. These include recent developments in synthetic organic chemistry, high-throughput recombinant production strategies, highresolution analytical methods, high-throughput screening options, ingenious drug delivery strategies and novel formulation preparations. Here, we will briefly describe the key methodologies and strategies used in the therapeutic peptide development processes with selected examples of the most recent developments in the field. The aim of this review is to highlight the viable options a medicinal chemist may consider in order to improve a specific pharmacological property of interest in a peptide lead entity and thereby rationally assess the therapeutic potential this class of molecules possesses while they are traditionally (and incorrectly) considered ‘undruggable’.


Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2237 ◽  
Author(s):  
P. R. Sarika ◽  
Paul Nancarrow ◽  
Abdulrahman Khansaheb ◽  
Taleb Ibrahim

Phenol–formaldehyde (PF) resin continues to dominate the resin industry more than 100 years after its first synthesis. Its versatile properties such as thermal stability, chemical resistance, fire resistance, and dimensional stability make it a suitable material for a wide range of applications. PF resins have been used in the wood industry as adhesives, in paints and coatings, and in the aerospace, construction, and building industries as composites and foams. Currently, petroleum is the key source of raw materials used in manufacturing PF resin. However, increasing environmental pollution and fossil fuel depletion have driven industries to seek sustainable alternatives to petroleum based raw materials. Over the past decade, researchers have replaced phenol and formaldehyde with sustainable materials such as lignin, tannin, cardanol, hydroxymethylfurfural, and glyoxal to produce bio-based PF resin. Several synthesis modifications are currently under investigation towards improving the properties of bio-based phenolic resin. This review discusses recent developments in the synthesis of PF resins, particularly those created from sustainable raw material substitutes, and modifications applied to the synthetic route in order to improve the mechanical properties.


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