scholarly journals Enhancement of the attitude dynamics capabilities of the spinning spacecraft using inertial morphing

2019 ◽  
Vol 124 (1276) ◽  
pp. 838-871
Author(s):  
P.M. Trivailo ◽  
H. Kojima
Keyword(s):  
Kinetic Energy ◽  
Elliptic Integral ◽  
Geometric Interpretation ◽  
The Body ◽  
Attitude Dynamics ◽  
Wide Audience ◽  
Multi Stage ◽  
Principal Axes ◽  
Compound Rotation ◽  
And Control

ABSTRACTIn the previous works by the authors, an efficient method of control of the inversion of the spinning spacecraft was proposed. This method was prompted by the Dzhanibekov’s Effect or Tennis Racket Theorem, which are often seen by many as odd or even mysterious. For the spacecraft, initially undergoing periodic flipping motion, proposed method allows to completely stop these flips by transferring the unstable motion into the regular stable spin. Similarly, the method allows activation of the flipping motion of the spacecraft, which is initially undergoing its stable spin. In this paper, spacecraft designs, which have inertial morphing capabilities, are considered and their advantages are further investigated. For general formulation, the ability of the spacecraft to change its inertial properties, associated with all three principal axes of inertia, are assumed. For simulation of these types of spacecraft systems, extended Euler’s equations are used and peculiar dynamics of the spacecraft is illustrated with a several study cases. Complex spacecraft attitude dynamics manoeuvres, using geometric interpretation, employing angular momentum spheres and kinetic energy ellipsoids, are considered in detail. Contributions of the inertial morphing to the changes of the shape of the kinetic energy ellipsoid are demonstrated and are related to the resultant various feature manoeuvres, including inversion and re-orientation. A method of reduction of the compound rotation of the spacecraft into a single stable predominant rotation around one of the body axes was proposed. This is achieved via multi-stage morphing and employing proposed instalment into separatrices. Implementation of the morphing control capabilities are discussed. For the periodic inversion motions, calculation of the periods of the flipping motion, based on the complete elliptic integral of the first kind, is performed. Flipping periods for various combinations of inertial properties of the spacecraft are presented in a systematic way. This paper discusses strategies to the increase or reduction the flipping and/or wobbling motions. A discovered asymmetric ridge of high periods for peculiar combinations of the inertial properties is discussed in detail. Numerous examples are illustrated with animations in virtual reality, facilitating explanation of the analysis and control methodologies to a wide audience, including specialists, industry and students.

scholarly journals The Motion of a Rigid Body in the Presence of a Gyrostatic : الحركات المغزلية السريعة لجسم متماسك في مجال قوة نيوتوني في حالة وجود العزم

2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Ghadir Ahmed Sahli
Keyword(s):  
Rigid Body ◽  
Degrees Of Freedom ◽  
Equations Of Motion ◽  
First Integral ◽  
Geometric Interpretation ◽  
The Body ◽  
Parameter Method ◽  
Principal Axes ◽  
Linear Autonomous System ◽  
Newtonian Force Field

In this study، the rotational motion of a rigid body about a fixed point in the Newtonian force field with a gyrostatic momentum  about the z-axis is considered. The equations of motion and their first integrals are obtained and reduced to a quasi-linear autonomous system with two degrees of freedom with one first integral. Poincare's small parameter method is applied to investigate the analytical peri­odic solutions of the equations of motion of the body with one point fixed، rapidly spinning about one of the principal axes of the ellipsoid of inertia. A geometric interpretation of motion is given by using Euler's angles to describe the orientation of the body at any instant of time.

Perbandingan Efek Suplementasi Tablet Tambah Darah Dengan Dan Tanpa Vitamin C Terhadap Kadar Hemoglobin Pada Ibu Hamil Dengan Usiakehamilan 16-32 Minggu Di Desa Keniten Kecamatan Mojo Kabupaten Kediri

2017 ◽  
Vol 3 (1) ◽  
pp. 76
Author(s):  
Siti Asiyah ◽  
Dwi Estuning Rahayu ◽  
Wiranti Dwi Novita Isnaeni
Keyword(s):  
Treatment Group ◽  
Vitamin C ◽  
Gestational Age ◽  
Group Treatment ◽  
Sampling Technique ◽  
Hemoglobin Level ◽  
The Body ◽  
Control Group ◽  
Fetal Organ ◽  
And Control

The needed of Iron Tablet in pregnancy was increase than mother who not pregnant.  That  cause of  high metabolism at the pregnancy for formed of  fetal organ and energy. One of effort for prevent anemia in mother pregnant with giving the Iron tablet and vitamin c. The reason of  this research in 4 June – 11 July 2014 is for compare the effect of  iron tablet suplementation with and without vitamin C toward Hemoglobin level in mother pregnant With Gestational Age Of 16-32 Weeks In Desa Keniten Kecamatan Mojo Kabupaten Kediri. This research method using comparative analytical.  Research design type of Quasy Eksperiment that have treatment group and control group. Treatment group will giving by Iron tablet and 100 mg vitamin C, and control group just giving by iron tablet during 21 days. Population in this research are all of mother pregnant with Gestational Age Of 16-32 Weeks with Sampling technique is  cluster random sampling is 29 mother pregnant. Comparison analysis of  iron tablet suplementation effect with and without vitamin C toward Hemoglobin level in mother pregnant With Gestational Age Of 16-32 Weeks, data analysis using Mann Whitney U-test and the calculated U value (44,5) less than U-table (51). So there was difference of iron tablet suplementation effect with and without vitamin C toward Hemoglobin level in mother pregnant With Gestational Age Of 16-32 Weeks Therefore, the addition of vitamin C on iron intake is needed to increase the uptake of iron tablets. When the amount of iron uptake increases, the reserves of iron in the body will also increase, so as to prevent anemia in pregnant women; Keywords : Iron Tablet (Fe), Vitamin C, Hemoglobin level, Mother Pregnant

In-vivo evaluation of lipid lowering ability of Chloris paraguaiensis extracts

2020 ◽  
Vol 7 (2) ◽  
pp. 21-24
Author(s):  
Pavani C H
Keyword(s):  
Medicinal Plants ◽  
Chemical Constituents ◽  
The Body ◽  
Lipid Lowering ◽  
Medical Systems ◽  
In Vivo Evaluation ◽  
Standard Drug ◽  
Anti Oxidant ◽  
And Control

Hyperlipidemia is the immediate results of the excessive fat intake in food. This results in the elevated levels of cholesterol and triglycerides in the blood. This leads to heart conditions like CAD, hypertension, congestive heart failure as risk factors which can be lethal. There are many drugs to treat and control the lipids levels in the body. These drugs are either designed to prevent LDL accumulation and VLDL synthesis. Some drugs also lower the elevated levels of saturated lipids in the body. But many drugs are known to cause side effects and adverse effects; therefore, alternatives to the drugs are the subjects for current investigations. Herbs and medicinal plants are used as treatment sources for many years. They have been used in the Indian medical systems like Ayurveda, Siddha etc. As the application of herbs in the treatment is growing, there is an urgent need for the establishment of Pharmacological reasoning and standardization of the activity of the medicinal plants. Chloris paraguaiensis Steud. is Poyaceae member that is called locally as Uppugaddi. Traditionally it is used to treat Rheumatism, Diabetes, fever and diarrhoea. The chemical constituents are known to have anti-oxidant properties and most of the anti-oxidants have anti-hyperlipidemic activity too. Since the plant has abundant flavonoid and phenol content, the current research focusses on the investigation of the anti-hyperlipidemic activity of the plant Chloris extracts. Extracts of Chloris at 200mg/kg showed a comparably similar anti hyperlipidemia activity to that of the standard drug. The extracts showed a dose based increase in the activity at 100 and 200mg/kg body weight.

Role of Rasayana in Prevention of COVID-19 - A Review

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 716-722
Author(s):  
Sneha Dhakite ◽  
Sadhana Misar Wajpeyi
Keyword(s):  
Immune System ◽  
Respiratory System ◽  
Viral Infections ◽  
Cost Effective ◽  
The Body ◽  
Healthy Life ◽  
Vital Functions ◽  
Healthy Life Style ◽  
And Control

The “Coronavirus disease 19 (COVID-19)” is caused by “Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)”, a newly discovered member of the Coronaviridae family of viruses which is a highly communicable. There is no effective medical treatment till date for Coronavirus disease hence prevention is the best way to keep disease away. Rasayana proved to be highly efficacious and cost effective for the Prevention and Control of viral infections when vaccines and standard therapies are lacking. Rasayana Chikitsa is one of the eight branches of Ashtanga Ayurveda which helps to maintain healthy life style. Rasayana improves immunity and performs many vital functions of human body. Vyadhikshamatva that is immune mechanism of the body is involved in Prevention of the occurrence of a new disease and it also decreases the virulence and progression of an existing disease. In COVID-19 the Respiratory system mainly get affected which is evident from its symptoms like cold, cough and breathlessness. Here the drugs help in enhancing immune system and strengthening functions of Respiratory system can be useful. For this purpose, the Rasayana like Chyavanprasha, Agastya Haritaki, Pippali Rasayana, Guduchi, Yashtimadhu, Haridra, Ashwagandha, Tulsi are used. Rasayana working on Respiratory system are best for Prevention of Coronavirus and boosting immune system. Rasayana Chikitsa can be effective in the Prevention as well as reducing symptoms of COVID-19.

scholarly journals The dynamic of body and brain co-evolution

2021 ◽  
pp. 105971232199468
Author(s):  
Paolo Pagliuca ◽  
Stefano Nolfi
Keyword(s):  
Morphological Traits ◽  
The Body ◽  
Morphological Variations ◽  
And Control ◽  
Selection Of

We introduce a method that permits to co-evolve the body and the control properties of robots. It can be used to adapt the morphological traits of robots with a hand-designed morphological bauplan or to evolve the morphological bauplan as well. Our results indicate that robots with co-adapted body and control traits outperform robots with fixed hand-designed morphologies. Interestingly, the advantage is not due to the selection of better morphologies but rather to the mutual scaffolding process that results from the possibility to co-adapt the morphological traits to the control traits and vice versa. Our results also demonstrate that morphological variations do not necessarily have destructive effects on robots’ skills.

scholarly journals Clinical and in Vivo Response Following Surgery or Surgery Plus Adjuvant Chemotherapy or Immunotherapy for Colorectal Carcinoma in a Rat Model

1983 ◽  
Vol 76 (10) ◽  
pp. 833-840 ◽  
Author(s):  
A K House ◽  
M A L Maley
Keyword(s):  
Body Weight ◽  
Adjuvant Chemotherapy ◽  
Surgical Excision ◽  
The Body ◽  
Recurrent Tumour ◽  
Mesenteric Node ◽  
And Control ◽  
Tumour Weight

Two cohorts of rats, 240 with colon cancer and 150 controls, were assessed clinically and immunologically for their response to tumour and its management which was either by surgical excision alone or by surgical excision combined with either adjuvant chemotherapy or immunotherapy. The histology and invasion characteristics were observed for similarity with those of human lesions. Metastases were found in liver, lymph nodes, the peritoneum or lungs in 27% of animals during follow up. Significantly fewer adjuvant-treated rats had metastases than those receiving surgery alone ( P < 0.05), and less total tumour weight was found in the adjuvant-treated rats at four ( P < 0.03) and six ( P < 0.001) weeks postoperatively. Animals in the adjuvant immunotherapy group survived longer than in either other group ( P < 0.001). The crude parameters of host response to tumour, body, spleen and mesenteric lymph node weight were recorded and the latter two indexed to body weight. The body weight of tumour and control rats increased significantly with time ( P < 0.04). The spleen and mesenteric node indices were significantly ( P < 0.04) greater in tumour than control rats and were varied by recurrent tumour growth and by the adjuvant treatment administered postoperatively.

scholarly journals Scalable co-optimization of morphology and control in embodied machines

2018 ◽  
Vol 15 (143) ◽  
pp. 20170937 ◽  
Author(s):  
Nick Cheney ◽  
Josh Bongard ◽  
Vytas SunSpiral ◽  
Hod Lipson
Keyword(s):  
Embodied Cognition ◽  
Initial Conditions ◽  
Control Policy ◽  
Sensorimotor Control ◽  
Body Plan ◽  
The Body ◽  
Test Bed ◽  
Local Optima ◽  
Close Coupling ◽  
And Control

Evolution sculpts both the body plans and nervous systems of agents together over time. By contrast, in artificial intelligence and robotics, a robot's body plan is usually designed by hand, and control policies are then optimized for that fixed design. The task of simultaneously co-optimizing the morphology and controller of an embodied robot has remained a challenge. In psychology, the theory of embodied cognition posits that behaviour arises from a close coupling between body plan and sensorimotor control, which suggests why co-optimizing these two subsystems is so difficult: most evolutionary changes to morphology tend to adversely impact sensorimotor control, leading to an overall decrease in behavioural performance. Here, we further examine this hypothesis and demonstrate a technique for ‘morphological innovation protection’, which temporarily reduces selection pressure on recently morphologically changed individuals, thus enabling evolution some time to ‘readapt’ to the new morphology with subsequent control policy mutations. We show the potential for this method to avoid local optima and converge to similar highly fit morphologies across widely varying initial conditions, while sustaining fitness improvements further into optimization. While this technique is admittedly only the first of many steps that must be taken to achieve scalable optimization of embodied machines, we hope that theoretical insight into the cause of evolutionary stagnation in current methods will help to enable the automation of robot design and behavioural training—while simultaneously providing a test bed to investigate the theory of embodied cognition.

PRE-MATERNAL ISOLATION EFFECTS ON BEHAVIOUR AND ENDOCRINE FUNCTION OF OFFSPRING

1969 ◽  
Vol 62 (2) ◽  
pp. 367-384 ◽  
Author(s):  
A. M. Sackler ◽  
A. S. Weltman ◽  
R. Schwartz ◽  
P. Steinglass
Keyword(s):  
Locomotor Activity ◽  
Growth Rates ◽  
Female Offspring ◽  
The Body ◽  
Endocrine Function ◽  
Male And Female ◽  
Isolation Stress ◽  
Developmental Growth ◽  
Body Weights ◽  
And Control

ABSTRACT This report was designed to determine combined effects of maternal endocrine imbalances and abnormal behaviour due to prolonged isolation stress of female mice on the behaviour, developmental growth rate and endocrine function of their offspring. Sixty female albino mice averaging 19 g were divided equally into isolated and control groups. The isolated females were housed singly; control females were maintained in groups of 2 mice per cage. After observation of behavioural and physiological effects characteristic of isolation stress in the test mice, all isolated and control mice were mated after a 6½ month experimental, isolation period. No differences were observed in fertility and fecundity of the two groups of mothers. Analyses of developmental growth rates of the litters of the isolated versus control mothers showed significantly lower body weights in the test offspring at 3 and 4 weeks of age. The body weights of the female offspring remained significantly lower from the 4th to 11th weeks. The effects on the body weights of the male offspring declined and were no longer statistically significant at the 5th to 11 weeks. Locomotor activity at 4½ and 8 weeks of age was markedly or significantly higher in the male and female mice from isolated mothers. Tail-blood samples taken prior to autopsy at 5 and 11 weeks of age revealed significant decreases in the total leukocyte and eosinophil counts of both sexes. At the two ages, the absolute and relative spleen and thymus weights of the male and female offspring were markedly and/or significantly lower than the values observed in counterpart young from control females. Significant decreases were also observed in the absolute gonadal organ weights of both sexes at 11 weeks of age. The various data indicated inhibited growth rates, heightened locomotor activity and evasiveness, as well as evidence of increased adrenocortical function in the offspring from test mothers. The gonadal weight decreases suggested retarded gonadal development. Further studies using split-litter techniques are required to differentiate the effects of prenatal endocrine imbalances versus postnatal maternal influence (i. e., nursing care) on the offspring.

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