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1 – 10 of 370Two leading contributors to cybernetics have recently died. This communication records matters that arose in correspondence with each of them. Professor Pesi Masani was much…
Abstract
Two leading contributors to cybernetics have recently died. This communication records matters that arose in correspondence with each of them. Professor Pesi Masani was much concerned with the adverse social consequences of modem technology, and a particular aspect of this affecting his native India is discussed. Dr Charles Musès believed that insight into basic aspects of biology would stem from study of cross‐kingdom (animal and plant) parasitism, though unfortunately he did not elaborate the basis of this. An example of human infection by a fungus that usually infests plants is quoted, and also findings from the literature on insect‐transmitted plant viruses. The latter suggest that viruses are truly able to span distinct kingdoms in ways that would certainly have interested Dr Musès.
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Esmaeel Khanmirza, Aghil Yousefi‐Koma and Bahram Tarvirdizadeh
The purpose of this paper is to develop a nonlinear control system for flight trajectory control of flapping Micro Aerial Vehicles (MAVs), subjected to wind.
Abstract
Purpose
The purpose of this paper is to develop a nonlinear control system for flight trajectory control of flapping Micro Aerial Vehicles (MAVs), subjected to wind.
Design/methodology/approach
In the dynamic study and fabrication of the MAV, biomimetic principles are considered as the best inspiration for the MAV's flight as well as design constraints. The blade element theory, which is a two‐dimensional quasi‐steady state method, is modified to consider the effect of MAV's translational and rotational velocity. A quaternion‐based dynamic wrench method is then developed for the dynamic system.
Findings
The flapping flight dynamics is highly nonlinear and the system is under‐actuated, so any linear control strategy fails to meet any desired maneuver for trajectory tracking. In this study, a controller with quaternion‐based feedback linearization method is designed for the dynamical averaged system. It is shown that the original system is bonded to a stable limit cycle with desired amplitude and the controller inputs are bounded.
Practical implications
The effectiveness of a synthesized controller is proved for the cruse and the Cuban‐8 maneuver.
Originality/value
The authors' major contribution is developing feedback linearization quaternion‐based controller and deriving some essential mathematics for implementing quaternion model in the synthesis of controller. A piezoelectric‐actuated wing model is developed for the control system. Results of cursing and turning modes of the flight indicate the stability of the flight. Finally, an appropriate controller is designed for the Cuban‐8 maneuver so that the MAV would follow the trajectory with a bounded fluctuation.
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María Teresa Signes-Pont, José Juan Cortés-Plana, Higinio Mora and Rafael Mollá-Sirvent
The purpose of this paper is to present a discrete compartmental susceptible-asymptomatic-infected-dead (SAID) model to address the expansion of plant pests. The authors examined…
Abstract
Purpose
The purpose of this paper is to present a discrete compartmental susceptible-asymptomatic-infected-dead (SAID) model to address the expansion of plant pests. The authors examined the case of Xylella fastidiosa in almond trees in the province of Alicante (Spain) to define the best eradication/contention protocol depending on the environmental parameters such as climatic factors, distance between trees, isolation of the plots, etc.
Design/methodology/approach
This approach considers the expansion of the disease among the almond trees orchards by means of a grid model. The cells of the grid represent a tree (or even a group of trees) that can be susceptible (healthy), asymptomatic (infected by the bacterium but without symptoms), infected or dead. When time passes, the status of the cells is determined by binary rules that update following both a neighborhood and a delay pattern. The model assumes that the environmental parameters have a crucial impact on the expansion of the disease, so a grid is assigned to each parameter to model the single effect caused by this parameter. The expansion is then the weighted sum of all the grids.
Findings
This proposal shows how the grid architecture, along with an update rule and a neighborhood pattern, is a valuable tool to model the pest expansion. This model has already been analyzed in previous works and has been compared with the corresponding continuous models solved by ordinary differential equations, coming to find the homologous parameters between both approaches. Thus, it has been possible to prove that the combination neighborhood-update rule is responsible for the rate of expansion and recovering/death of the illness. The delays (between susceptible and asymptomatic, asymptomatic and infected, infected and recovered/dead) may have a crucial impact on both the peak of infected and the recovery/death rate. This theoretical model has been successfully tested in the case of the dissemination of information through mobile social networks and is also currently under study in the case of expansion of COVID-19.
Originality/value
This work develops a new approach for the analysis of expansion of plant pests. This approach provides both behavioral variability at the cell level (by its capability to modify the neighborhood and/or the update rule and/or the delays) and modularity (by easy scaling the number of grids). This provides a wide range of possibilities to deal with realistic scenarios.
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“It is generally accepted that the food industry must be scientifically based to cope with the problems, particularly of public health, which arise as new processes of growing…
Abstract
“It is generally accepted that the food industry must be scientifically based to cope with the problems, particularly of public health, which arise as new processes of growing, manufacturing, packaging and preserving food depart even further from traditional ways.”
Millions of the British people have for some years now been struggling valiantly to live with hard times, watching them day by day grow worse but always hopefully that the cloud…
Abstract
Millions of the British people have for some years now been struggling valiantly to live with hard times, watching them day by day grow worse but always hopefully that the cloud had a silver lining; that one day, reason and a sense of direction would prevail. Tyranny in many forms is a feature of history; the greatest epics have been risings of ordinary people to overthrow it. The modern form of tyranny is that of Money; the cruel and sinister ways in which it can be obtained and employed and the ineffectiveness of any measures taken to control the evils which result. Money savings over the years and the proverbial bank book, once the sure safeguard of ordinary people, are whittled away in value, never to recover. Causes always seemed to be contained within the country's own economy and industrial practices, and to this extent should have been possible of control. The complex and elaborate systems constructed by the last Government were at least intended for the purpose, but each attempt to curb excessive demands for more money, more and more for doing less and less— the nucleus of inflation—produced extreme reactions, termed collectively “industrial strife”. Every demand met without compensatory returns in increased work, inevitably led to rises in prices, felt most keenly in the field of food and consumer goods. What else would be expected from such a situation?
Yanli Lu, Yao Yao, Shuang Li, Qian Zhang and Qingjun Liu
Using the remarkable olfaction ability, insects can sense trace amounts of host plant volatiles that are notorious for causing severe damage to fruits and vegetables and in…
Abstract
Purpose
Using the remarkable olfaction ability, insects can sense trace amounts of host plant volatiles that are notorious for causing severe damage to fruits and vegetables and in consequence the industry. The purpose of the paper is to investigate the interactions between olfactory proteins, odorant-binding proteins (OBPs) and host plant volatiles through the developed olfactory biosensors. It might be helpful to develop novel pest control strategies.
Design/methodology/approach
Using the successfully expressed and purified OBPs of the oriental fruit fly Bactrocera dorsalis, a biosensor was developed by immobilizing the proteins on interdigitated electrodes through nitrocellulose membrane. Based on electrochemical impedance sensing, benzaldehyde emitted by the host plants, such as Beta vulgaris, was detected, which could be used to investigate and analyze the mechanisms of pests’ sense of chemical signals. The relative decreases of charge transfer resistances of the sensor were proportional to the odorant concentrations from 10−7 M to 10−3 M. Meanwhile, the interactions between OBPs and benzaldehyde were studied through the process of molecular docking.
Findings
The paper provides a pest OBPs-based biosensor that could sensitively detect the host odorants benzaldehyde. Meanwhile, the most related amino acids of OBPs that bind to host plant volatiles can be distinguished with molecular docking.
Originality/value
An olfactory biosensor was developed to explore interactions and mechanism between the pest OBPs and benzaldehyde, which showed promising potentials for small organic molecule sensing. Simultaneously, it might be helpful for novel pest control strategies.
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Reports of a number of countries imposing a limited ban on the use of D.D.T. have appeared from time to time in the B.F.J., but in the last few months, what was a trickle seems to…
Abstract
Reports of a number of countries imposing a limited ban on the use of D.D.T. have appeared from time to time in the B.F.J., but in the last few months, what was a trickle seems to have become an avalanche. In Canada, for example, relatively extensive restrictions apply from January 1st, permitting D.D.T. for insect control in only 12 agricultural crops, compared with 62 previously; there is a reduction of maximum levels for most fruits to 1 ppm. Its cumulative properties in fat are recognized and the present levels of 7 ppm in fat of cattle, sheep and pigs are to remain, but no trace is permitted in milk, butter, cheese, eggs, ice cream, other dairy products, nor potatoes. A U.S. Commission has advised that D.D.T. should be gradually phased out and completely banned in two years' time, followed by the Report of the Advisory Committee on Pesticides and Other Toxic Chemicals recommending withdrawal in Britain of some of the present uses of D.D.T. (also aldrin and dieldrin) on farm crops when an alternative becomes available. Further recommendations include an end to D.D.T. in paints, lacquers, oil‐based sprays and in dry cleaning; and the banning of small retail packs of D.D.T. and dieldrin for home use in connection with moth‐proofing or other insect control. The Report states that “domestic users are often unaware that using such packs involve the risk of contaminating prepared food immediately before it is eaten”.
Michael W. Ross and Amy Jo Harzke
This paper aims to explore how the TECH Model (testing for and treating infectious diseases and vaccination; environmental modification to prevent disease transmission; chronic…
Abstract
Purpose
This paper aims to explore how the TECH Model (testing for and treating infectious diseases and vaccination; environmental modification to prevent disease transmission; chronic disease identification and treatment; and health maintenance and education) can be used for assessing and achieving healthy prisons.
Design/methodology/approach
This paper explores the concepts of “health in prison” and “healthy prisons” in the context of recent research and guidance. The paper then considers the TECH Model as an approach to achieving healthy prisons.
Findings
Under each of the four TECH Model domains are tasks to achieve a healthy prison. For prisons with poor or no resources, each domain contains steps that will improve prison health and move towards a healthy prison for both prisoners and staff. Implementation can thus be “low‐TECH” or “high‐TECH” depending on the setting and the available resources and the model is specifically designed to provide options for resource‐poor as well as resource‐rich correctional settings.
Originality/value
The TECH Model is a first step in characterizing the components of a healthy prison and the processes to achieve this. This Model could be implemented in all levels of prisons internationally.
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The last two years have witnessed what may justly be described as a revolutionary change in the packaging and marketing of goods, of which pre‐packed food constitutes a…
Abstract
The last two years have witnessed what may justly be described as a revolutionary change in the packaging and marketing of goods, of which pre‐packed food constitutes a substantial part, but as far as public reaction goes, it has largely been a silent witness. There has been none of the outcry such as accompanied metrication, sufficient to call a halt to the process, and especially to the introduction of the decimal currency, of which most shoppers are convinced they were misled, “conned”. Every effort to make the changeover as smooth as possible was made; included was the setting up within the Department of Trade of a National Metrological Co‐ordinating Unit charged with co‐ordinating the work of 91 local weights and measures authorities in Great Britain in enforcing the new law, the Weights and Measures Act, 1979. This Act replaced the net or minimum system of the old law, the traditional system, re‐enacted in the Weights and Measures Act, 1963 with the average system, implementing EEC Directives and bringing weights and measures into line with Member‐states of the European Community.
Focuses on the direct and indirect impact of environmental abuse on human wellbeing. In some instances, the impact of environmental abuse on human health is not still unknown…
Abstract
Focuses on the direct and indirect impact of environmental abuse on human wellbeing. In some instances, the impact of environmental abuse on human health is not still unknown, merely being subject to scientific suspicion. This would suggest caution and the need for preventive measures to be applied. The threat to human health from environmental factors is not an isolated problem that exists on a national level. There are environmental factors that affect human health on a global level or are so widespread as to be considered global problems. Other environmental problems cross national boundaries and achieve regional importance.
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