scholarly journals Silicon Eye

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
S. Thuvvakkadan ◽  
V. J. Nair
Keyword(s):  
Effective Interaction ◽  
Drainage System ◽  
Modern Medicine ◽  
Primary Circuit ◽  
Retinal Layer ◽  
Chemical Synapse ◽  
Secondary Circuit ◽  
Chemical Synapses ◽  
Effective Drainage ◽  
Electrical Impulses

Silicon eye can be otherwise called as a complete eye implant. The project overview is given in brief by the description of main components. Here in the silicon eye, a biconcave gel lens is used in connection with a micro controller. A porous silicon nano photodiode is placed before the gel lens. This specially designed transparent diode will help in identifying the intensity of light receiving in the beginning of the processing chain. An effective drainage system (with the help of two valves) will control the working of gel lens. All these components together form the primary circuit to enable the process of auto focusing. The micro controller is connected with all components of the system. The primary circuit is connected to a secondary circuit which consists of an artificial silicon retina and a chemical synapse. By the combined and co-ordinate working of both these will enable vision. The power supply, which all the electrical components here need is given by a series of nano paper batteries placed beneath the retinal layer (carbon nano tubes can also be implemented instead or along with it). The converted electrical impulses (from intensity of light received) will be carried to the visual area of brain through optic nerve by the effective interaction with a number of artificial chemical synapses. Finally this silicon eye will be an effective implant for the damaged eye. And we are sure that this will be a great breakthrough in the modern medicine.

New Concept for a Thoracic Drainage System Using Magnetic Actuation

2019 ◽  
Vol 26 (6) ◽  
pp. 705-711
Author(s):  
Daisuke Taniguchi ◽  
Keitaro Matsumoto ◽  
Yoshihiro Kondo ◽  
Tomoshi Tsuchiya ◽  
Ikuo Yamamoto ◽  
...  
Keyword(s):  
Abdominal Cavity ◽  
Drainage System ◽  
Magnetic Actuation ◽  
Thoracic Cavity ◽  
Common Procedure ◽  
Thoracic Drainage ◽  
Drain Fluid ◽  
Laboratory Trial ◽  
General Surgeons ◽  
Effective Drainage

Objectives. Thoracic drainage is a common procedure to drain fluid, blood, or air from the pleural cavity. Some attempts to develop approaches to new thoracic drainage systems have been made; however, a simple tube is often currently used. The existing drain presupposes that it is placed correctly and that the tip does not require moving after insertion into the thoracic cavity. However, in some cases, the drain is not correctly placed and reinsertion of an additional drain is required, resulting in significant invasiveness to the patient. Therefore, a more effective drainage system is needed. This study aimed to develop and assess a new thoracic drain via a collaboration between medical and engineering personnel. Methods. We developed the concept of a controllable drain system using magnetic actuation. A dry laboratory trial and accompanying questionnaire assessment were performed by a group of thoracic and general surgeons. Objective mechanical measurements were obtained. Porcine experiments were also carried out. Results. In a dry laboratory trial, use of the controllable drain required significantly less time than that required by replacing the drain. The average satisfaction score of the new drainage system was 4.07 out of 5, indicating that most of the research participants were satisfied with the quality of the drain with a magnetic actuation. During the porcine experiment, the transfer of the tip of the drain was possible inside the thoracic cavity and abdominal cavity. Conclusion. This controllable thoracic drain could reduce the invasiveness for patients requiring thoracic or abdominal cavity drainage.

scholarly journals Synaptic polarity and sign-balance prediction using gene expression data in the Caenorhabditis elegans chemical synapse neuronal connectome network

2020 ◽  
Vol 16 (12) ◽  
pp. e1007974
Author(s):  
Bánk G. Fenyves ◽  
Gábor S. Szilágyi ◽  
Zsolt Vassy ◽  
Csaba Sőti ◽  
Peter Csermely
Keyword(s):  
Gene Expression ◽  
Caenorhabditis Elegans ◽  
Gene Expression Data ◽  
Receptor Gene ◽  
Directed Network ◽  
Chemical Synapse ◽  
Expression Data ◽  
Chemical Synapses ◽  
Theoretical Analyses ◽  
Receptor Gene Expression

Graph theoretical analyses of nervous systems usually omit the aspect of connection polarity, due to data insufficiency. The chemical synapse network of Caenorhabditis elegans is a well-reconstructed directed network, but the signs of its connections are yet to be elucidated. Here, we present the gene expression-based sign prediction of the ionotropic chemical synapse connectome of C. elegans (3,638 connections and 20,589 synapses total), incorporating available presynaptic neurotransmitter and postsynaptic receptor gene expression data for three major neurotransmitter systems. We made predictions for more than two-thirds of these chemical synapses and observed an excitatory-inhibitory (E:I) ratio close to 4:1 which was found similar to that observed in many real-world networks. Our open source tool (http://EleganSign.linkgroup.hu) is simple but efficient in predicting polarities by integrating neuronal connectome and gene expression data.

Seepage through Earth Dams with Chimney Drain on Pervious Foundation

2012 ◽  
Vol 452-453 ◽  
pp. 538-542 ◽  
Author(s):  
Abdelkader Djehiche ◽  
Rekia Amieur ◽  
Mustafa Gafsi
Keyword(s):  
Experimental Study ◽  
Flow Rate ◽  
Drainage System ◽  
Earth Dam ◽  
Earth Dams ◽  
Drainage Systems ◽  
The Earth ◽  
Excess Water ◽  
Effective Drainage

This paper presents an experimental study of a homogenous earth dam. The work is focused to the search of solutions of problems encountered in the earth dams after their construction. One of the major problems is the choice and design of systems of drainage. The effective drainage system to prevent harmful accumulations of excess water is one of the most important roles of dams. Efficient drainage systems can improve the safety of earth dams. The paper presented herein reports the results obtained from the experimental study. Empiric relations have been obtained which can be help in the control of the flow rate in the chimney drain of the earth dams on pervious foundation, which can increase safety earth dams

scholarly journals Inductive powering of subcutaneous stimulators: key parameters and their impact on the design methodology

2016 ◽  
Vol 26 (2) ◽  
Author(s):  
Carmen Godfraind ◽  
Adrien Debelle ◽  
Laurent Lonys ◽  
Vicente Acuña ◽  
Pascal Doguet ◽  
...  
Keyword(s):  
System Design ◽  
Medical Devices ◽  
Design Methodology ◽  
Design Procedure ◽  
Power Source ◽  
Critical Parameters ◽  
Primary Circuit ◽  
System Efficiency ◽  
Secondary Circuit ◽  
Implantable Medical Devices

Inductive powering of implantable medical devices involves numerous factors acting on the system efficiency and safety in adversarial ways. This paper lightens up their role and identifies a procedure enabling the system design. The latter enables the problem to be decoupled into four principal steps: the frequency choice, the magnetic link optimization, the secondary circuit and then finally the primary circuit designs. The methodology has been tested for the powering system of a device requirering a power of 300mW and implanted at a distance of 15 to 30mm from the outside power source. It allowed the identification of the most critical parameters. A satisfying efficiency of 34% was reached at 21mm and tend to validate the proposed design procedure.

Magnetic Properties of Materials Used in Electric Arc Welding and Surfacing

2018 ◽  
Vol 938 ◽  
pp. 33-40
Author(s):  
Alexander D. Razmyshlyaev ◽  
Marina V. Ahieieva ◽  
Elena V. Lavrova
Keyword(s):  
Magnetic Properties ◽  
Magnetic Fields ◽  
Arc Welding ◽  
Primary Circuit ◽  
Secondary Circuit ◽  
Electrode Wire ◽  
Electric Arc Welding ◽  
Materials Used ◽  
Submerged Arc ◽  
Welding Materials

It was experimentally established earlier that the increment of the electrode wire melting coefficient at submerged arc welding and surfacing with magnetic fields action (with equal parameters of the welding mode) depends on the chemical composition of the wires. It is suggested that this effect depends on the magnetic properties of the welding materials, i.e. electrode wire and base metal. To measure the magnetic properties of welding materials, a method has been developed in which the magnetic properties of welding materials on samples are investigated. The samples were made in the form of tori, on which the primary and secondary windings were placed. The primary circuit contains an ammeter and a voltmeter, as well as a wattmeter that allows to take into account losses in the sample on hysteresis and Foucault currents, and the secondary circuit contains a voltmeter. Experimental data on the magnetic properties of some welding and surfacing wires, as well as of base metals, are obtained. A simplified method is proposed, in which torus samples are also used, but on which only one winding is placed, over which a direct current is flowed. The value of the increment of the electrode wire melting coefficient at arc welding with the action of magnetic fields increases with increasing their magnetic permeability.

Environmental Assisted Fatigue and EDF 900 MWe PWRs Fleet: Towards an Exemption of Environmental Effects Consideration for Secondary Circuit Components

2018 ◽  
Author(s):  
Sam Cuvilliez ◽  
Gaëlle Léopold ◽  
Thomas Métais
Keyword(s):  
Environmental Effects ◽  
Nuclear Power ◽  
Power Plants ◽  
Fatigue Loading ◽  
Degradation Process ◽  
Fatigue Curve ◽  
Primary Circuit ◽  
Secondary Circuit ◽  
Technical Specifications ◽  
Circuit Components

Environmentally Assisted Fatigue (EAF) is receiving nowadays an increased level of attention for existing Nuclear Power Plants (NPPs) as utilities are now working to extend their life. In the wake of numerous experimental fatigue tests carried out in air and also in a PWR environment, the French RCC-M code [1] has recently been amended (in its 2016 edition) with two Rules in Probatory Phase (RPP), equivalent to ASME code-cases, “RPP-2” and “RPP-3” [2] [3]. RPP-2 consists of an update of the design fatigue curve in air for stainless steels (SSs) and nickel-based alloys, and is also associated with RPP-3 which provides guidelines for incorporating the environmental penalty “Fen” factor in fatigue usage factor calculations. Alongside this codification effort, an EAF screening has recently been carried out within EDF DT [4] on various areas of the primary circuit of the 900 MWe plants of the EDF fleet. This screening led to the identification of a list of 35 “sentinel locations” which are defined as areas most prone to EAF degradation process. These locations will be subjected to detailed EAF analysis in the stress report calculations (according to the above-mentioned RCC-M code cases) for the fourth decennial inspection of the 900 MWe (VD4 900 MWe) power plants. The potential impact of EAF on the secondary circuit components is another question to address in anticipation of the VD4 900 MWe, as they may be considered as class 1 or class 2 equipment for RCC-M application according to the equipment specification. This paper presents the approach proposed by EDF towards an exemption of environmental effects consideration for secondary circuit components. The argument is first based on a review of experimental campaigns led in Japan and France (respectively on fatigue test specimens and at the component scale) which indicate a Dissolved Oxygen (DO) content threshold below which environmental effects are almost inexistent. The (conservative) value of 40 ppb has been selected consistently with NUREG/CR-6909 revision 0 [5]. The second part of the argument is built, on the one hand, on the analysis of the EDF Technical Specifications for Operation (STE) which narrows the scope of the study only to unit outages, and, on the other hand, on the analysis of 5 years of operations of all 900 MWe plants of the EDF fleet (equivalent to 170 reactor-years). It has been shown that the DO content rarely exceeded the 40 ppb threshold in the secondary coolant, and that in this case, the considered locations were not submitted to any fatigue loading.

scholarly journals I. On magneto-electric induction in liquids and gases.—Part I. production of induced currents in electrolytes

1878 ◽  
Vol 26 (179-184) ◽  
pp. 40-43
Keyword(s):  
Sulphuric Acid ◽  
Magnetic Force ◽  
Primary Circuit ◽  
Rubber Tube ◽  
Secondary Circuit ◽  
Negative Results ◽  
Electric Induction ◽  
The Subject ◽  
Induced Currents ◽  
Solid Conductors

This paper contains an account of an experimental inquiry into the production of induced currents in liquids by magneto-electric induction. Faraday examined one such case of induction, in which a conducting liquid was used as a secondary circuit. He coiled round the armature of an electromagnet an india-rubber tube filled with dilute sulphuric acid, and found, on making and breaking the primary circuit, the induced currents generated in it, as in the case of metallic conductors; but he could not obtain any effect when brine, sulphuric acid, or other solutions were rotated in basins over a magnet, or enclosed in tubes and passed between the poles. He failed also to detect any magneto-electric current in water flowing across the earth’s lines of magnetic force (viz. in the river Thames). Since the reason for these negative results is not at once obvious, it seemed desirable to repeat and extend them to other cases, so that, if possible, the analogy of electrolytic with solid conductors might, in respect to magneto-electric induction, be completed. In addition, the subject involves the interesting question of the magneto-electric phenomena accompanying the flow of ocean-currents and other large masses of water.

The Water Ingress Mass Analysis on Steam Generator Heat-Exchange Tube Rupture Accident of High Temperature Gas-Cooled Reactor

2009 ◽  
Author(s):  
Yan Wang ◽  
Yanhua Zheng ◽  
Fu Li ◽  
Lei Shi ◽  
Zhiwei Zhou
Keyword(s):  
High Temperature ◽  
Heat Exchange ◽  
Steam Generator ◽  
Mechanical Load ◽  
Radioactive Isotopes ◽  
Primary Circuit ◽  
Secondary Circuit ◽  
Water Ingress ◽  
Heat Exchange Tube ◽  
High Temperature Gas

The module high temperature gas-cooled reactor (HTGR) is an advanced reactor with high safety level. The steam generator heat-exchange tube rupture (SGTR) accident (or water ingress accident) is an important and particular accident which will result in water ingress to the primary circuit of reactor. Water ingress may, in turn, result in chemical reaction of graphite fuel and structure with water, causing release of radioactive isotopes and generation of explosive gaseous in large quantity. The analysis of SGTR is significant for verifying the inherent safety characteristics of HTGR. One of the key factors is to estimate the amount of water ingress mass which is used to evaluate the severity of the accident consequence. The 200MWe high temperature gas-cooled reactor, which is designed by the Institute of Nuclear and New Energy Technology of Tsinghua University, is selected as an example to analyze. The accident scenarios of double-ended rupture of both single and two heat-exchange tubes at the inlet and outlet of steam generator are simulated respectively by RETRAN-02. The results show that the amount of water ingress mass is related to the break location, the number of ruptured tubes (or the break size). The greater the number of ruptured tubes or the break size, the larger the amount of water ingress mass. It is important to design the draining pipe line with reasonable diameter, which should be optimized based on economy and safety considerations for preventing large water ingress to the reactor primary circuit, restricting the change rate of mechanical load on SG, and reducing the radioactive isotopes release to the secondary circuit.

scholarly journals Influence of Deformation and Instability of Borehole on Gas Extraction in Deep Mining Soft Coal Seam

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xue-Bo Zhang ◽  
Shuai-Shuai Shen ◽  
Xiao-Jun Feng ◽  
Yang Ming ◽  
Jia-jia Liu
Keyword(s):  
Pressure Loss ◽  
Drainage System ◽  
Suction Pressure ◽  
Coal Seams ◽  
Gas Drainage ◽  
Soft Coal ◽  
Instability Modes ◽  
Deformation Instability ◽  
Effective Drainage ◽  
Drainage Effect

To study the effects of the three deformation instability modes of gas drainage borehole on gas drainage, the deformation instability mechanism of soft coal seams is analyzed, three deformation instability modes are proposed for soft coal seams, namely, complete holes, collapse holes, and plug holes, and a solid-fluid coupling model incorporating dynamic change of borehole suction pressure is established. The results of the study show the following. (1) When there is no borehole deformation (i.e., complete borehole), the suction pressure loss of drainage system in the borehole is very small, whose effect on gas drainage can be neglected. (2) In case of borehole collapse, the suction pressure loss is big at the collapse segment, and the total suction pressure loss of the drainage system in the borehole is bigger than that in the complete hole. However, it is smaller than the suction pressure of the drainage system and exerts limited effect on gas drainage. As the borehole collapse deteriorates, the effective drainage section of the borehole becomes smaller, while the suction pressure loss in the borehole increases continuously; thus, the gas drainage effect continuously worsens. (3) In case of plug hole, a continuous medium forms between the plug segment coal body and the surrounding coal seam, the plug segment drainage pressure turns into coal-bed gas pressure, and effective drainage length of the borehole shortens, seriously affecting the gas drainage effect. The study carries important theoretical guiding significance for improving gas drainage effect and effectively preventing gas disasters.

scholarly journals Theoretical Analysis of Coupled Modified Hindmarsh-rose Model Under Transcranial Magnetic-acoustic Electrical Stimulation

2022 ◽  
Vol 16 ◽  
pp. 610-617
Author(s):  
Liang Guo ◽  
Shuai Zhang ◽  
Jiankang Wu ◽  
Xinyu Gao ◽  
Mingkang Zhao ◽  
...  
Keyword(s):  
Nervous System ◽  
Electrical Stimulation ◽  
Modulation Frequency ◽  
Ultrasonic Waves ◽  
Neuronal Firing ◽  
Electrical Synapse ◽  
Discharge Frequency ◽  
Neural Network Modeling ◽  
Chemical Synapse ◽  
Chemical Synapses

Transcranial magnetic-acoustic electrical stimulation (TMAES) is a new technology with ultrasonic waves and a static magnetic field to generate an electric current in nerve tissues to modulate neuronal firing activities. The existing neuron models only simulate a single neuron, and there are few studies on coupled neurons models about TMAES. Most of the neurons in the cerebral cortex are not isolated but are coupled to each other. It is necessary to study the information transmission of coupled neurons. The types of neuron coupled synapses include electrical synapse and chemical synapse. A neuron model without considering chemical synapses is not comprehensive. Here, we modified the Hindmarsh-Rose (HR) model to simulate the smallest nervous system—two neurons coupled electrical synapses and chemical synapses under TMAES. And the environmental variables describing the synaptic coupling between two neurons and the nonlinearity of the nervous system are also taken into account. The firing behavior of the nervous system can be modulated by changing the intensity or the modulation frequency. The results show that within a certain range of parameters, the discharge frequency of coupled neurons could be increased by altering the modulation frequency, and intensity of stimulation, modulating the excitability of neurons, reducing the response time of chemical postsynaptic neurons, and accelerating the information transferring. Moreover, the discharge frequency of neurons was selective to stimulus parameters. These results demonstrate the possible theoretical regulatory mechanism of the neurons' firing frequency characteristics by TMAES. The study establishes the foundation for large-scale neural network modeling and can be taken as the theoretical basis for TMAES experimental and clinical application.

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