...Role of calcium in synapse transmission Calcium is a natural mineral that is supposed to be ingested into the body by human beings in order to have a healthy life.Calcium has a role in maintaining the health of the skin, bones and cartilages, muscle coordination and ultimately the central nervous system (CNS).This means that humans cannot live without calcium (Xu, J et al), but it is only needed in small amounts, to the tune of milligrams. A synapse is a space between two neurons in which neurotransmitters are released from the presynaptic neurons to exert an effect on the subsequent postsynaptic neuron.An action potential is generated in the pre-synaptic neuron by generating the influx of Na+ through the sodium channels and an efflux of the K+ ions via the Potassium channels.The action potential at the presynaptic terminal, triggers the influx of calcium into the terminal axon. The influx of calcium plays a functional role in the release of neurotransmitters from the presynaptic vesicles into the synaptic cleft. The experiment performed by Katz and Ricardo Melidi showed that presynaptic terminals that are treated with tetrodotoxin( binds sodium) are still capable of generating prolonged action potentials. The current was flowing through calcium channels instead of sodium. Another experiment by rodolfo llinas indicated presence of voltage gated calcium channels in presynaptic terminals. The experiment was carried out by using giant squid axon, confirmed the presence of...
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...Donald Hebb * Wanted to be a Writer Unlike Physicist Parents * At 33 was a Fellow at Montreal Neurological Institute * Absent Stimulation Causes Deterioration and Hallucinations * First Non-American to Win APA Distinguished Scientific Contribution Award * Had an Award for Canadian Scientists Named after Himself Donald Hebb decided at an early age he did not want to be a Physicist like his parents. He had other aspirations, he wanted to write and study. At the age of 33, Hebb received a position at the Montreal Neurological Institute as a research fellow (Olson & Hergenhahn, 2009). The research Hebb conducted ultimately contributed greatly to the modern knowledge of the brain. He discovered, when there is an absence of stimulation the resulting product is the brain has more difficulty in its ability to problem solve and even to concentrate (Olson & Hergenhahn, 2009). The absence causes deterioration in the ability to do things quickly and efficiently, causing extreme difficulty. Hebb has even reported a few people who said they had experienced hallucinations from the absence of stimulation (Olson & Hergenhahn, 2009). Hebb’s research was extremely helpful in the studies of airplane pilots and of truck drivers. Many of these workers had reported having hallucinations while on the job. Hebb discovered the hallucinations were due to the fact they were not experiencing enough mental stimulation to keep their brains alert and active. From the age...
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...2 Features · · · · 12 HT12A/HT12E Series of Encoders Minimum transmission word - Four words for the HT12E - One word for the HT12A Built-in oscillator needs only 5% resistor Data code has positive polarity Minimal external components HT12A/E: 18-pin DIP/20-pin SOP package Operating voltage - 2.4V~5V for the HT12A - 2.4V~12V for the HT12E Low power and high noise immunity CMOS technology Low standby current: 0.1mA (typ.) at VDD=5V HT12A with a 38kHz carrier for infrared transmission medium · · · · · Applications · · · · Burglar alarm system Smoke and fire alarm system Garage door controllers Car door controllers · · · · Car alarm system Security system Cordless telephones Other remote control systems General Description The 212 encoders are a series of CMOS LSIs for remote control system applications. They are capable of encoding information which consists of N address bits and 12-N data bits. Each address/data input can be set to one of the two logic states. The programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium upon receipt of a trigger signal. The capability to select a TE trigger on the HT12E or a DATA trigger on the HT12A further enhances the application flexibility of the 212 series of encoders. The HT12A additionally provides a 38kHz carrier for infrared systems. Selection Table Function Address Address/ Data Oscillator No. Data No. No. Part No. HT12A HT12E 8 8 0 4 4 0 455kHz...
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...The differential was first invented in China, in the third century,A.D. After turning a car the outside wheel has to turn faster then the inside one in order to cover the greater distance. That is why two wheels are not driven at a same speed. So we need a differential gear. A car differential is a place halfway between the wheels, on either the front or both axes. Main mechanisms: Wheels receive power from the motor via drive shaft. The power receiving wheels which makes the vehicle move fowrord are called as the drive wheels. Wheels receive power from the motor via drive shaft. The main function of the differential gear is to allow the drive wheels to turn at different Rpm while from the engine. The main characterics of differential is to, * To aim the engine power at wheels. * To transmit the power to the wheels while allowing them to rotate at differential speeds. the left wheel has to travel more distance compared to the right wheel. If the wheels where connected using a soil shaft. The wheels where connected using a soil shaft. The wheels would have to slip to accomplish the turn. The mechanism in a differential allows left and right wheels to turn at different Rpm, while transferring power to both the wheels. Differential parts: There are three types of gear available, Pinion drive gear: Transfers power from the drive shaft to the ring gear. Ring gear: Transfers power to the differential case assembly Side/Spider gears: Helps both wheels to turn...
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...Copper is the most used cabling solution in the market at the moment due to its ease of use and its price. Even the equipment is substantially cheaper to buy than other means of transmission. Copper cabling utilizes a single or multiple strands of copper to transmit data from one end to the other. Copper is broken up amongst several different categories each with their own set of improvements and flaws ranging from difficulty of installation to cost. The lower the category the more prone to interference there is like EMI’s and RFI’s. Electromagnetic interference from other cables in the location like power cords or other data connections. And RFI Radio frequency spectrum interference although the higher categories like Cat 7 are less prone to such interference a coper cabling solution is not 100 percent protected from such external interferences. Copper does have some limitations in how long a data signal can be sent without it becoming lost or the signal becoming too weak to make a proper connection which is around the 1000 feet or 305 meter range. Fiber optic on the other hand is much more expensive and as such so are the tools used for installation. Fiber optic is compiled of a core which can resemble glass in its form and a laser or diode that emits a light from one end to another enabling data transmission. Fiber is the best solution in speed and range that data can be transmitted. There are two different types of fiber optic cabling one being multi-mode and the other being single-mode...
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...complex and interesting part of any vehicle. A car can be broken down into three major mechanical components; the internal combustion engine which is the vehicles power source, the transmission which is its gearing system, and the rear differential axle which applies the power to the road. The internal combustion engine is the cars main power source. The engine is a series of pistons and rods housed inside an engine block. The engines pistons and rods are then rotated by a crankshaft at a high rate of speed through the power of internal combustion. Gasoline is then injected into an intake, where it blends with just the right amount of air to combust upon contact with a spark produced by a spark plug. This explosion then pushes the piston down, which in turn pushes another piston attached to the crankshaft back up. The rotating crankshaft then spins a flywheel attached to it, which transfers the power to the transmission. A transmission is a cars gearing system. It uses a sequence of gears to control the engines speed and revolutions. All engine have a red line, a maximum rpm value above which the engine cannot go without exploding. Depending on the engine the values may vary up or down. Different engines will have different power bands where the power is designed to be. The job of any transmission is to allow the driver to use these bands by shifting to designated gearing ratios to the engines full gearing potential. As the flywheel spins, it is engaged by a...
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...CHAPTER 1 INTRODUCTION 1.1 Problem Definition The rated power generated from the engine of a heavy duty vehicle can only become useful when effectively transmitted from the engine via the fly wheel to the transmission system of the truck and finally to the final drive. The propeller shaft or the drive shaft which is the mechanical component used for transmitting torque and rotation is used in transmitting these generated power to the final drive. However, when the Ghana Armed Forces introduced the Chinese made Dong Feng trucks which are five ton troop carrying vehicles (TCVs) for its operations, their propeller shafts recorded a high rate of failure. This inevitably affected the morale of troops and the operations of the Ghana Armed Forces. Some drivers of the truck fearing the propeller shaft failure could result in accident, hanged nylon rope or chain under the trucks to prevent a failed shaft from striking the ground. Below are pictures to that effect. This project therefore aims at identifying the causes of the failures of propeller shafts and recommend mitigating measures to them. Fig. 1.1 Nylon Rope Beneath the Propeller Shaft 1.2 Objectives The objectives of this project work are: * To identify the causes of propeller shaft failure of heavy duty trucks at the Base Workshop. * To recommend mitigating and preventive measures to the problems. 1.3 Justification It is anticipated that the findings of this project will...
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...Signs You Shouldn't Ignore Concerning Your Transmission As you may know, your transmissions is one of the main components of your vehicle. It is what keeps your car moving as well as helps hold it in place. Therefore, if it starts acting up, you need to get it looked at immediately. But, how do you know if it is acting up. Below you will find a few signs that should never be ignored. Transmission or Clutch Slipping This is one of the most common transmission issues, yet it is also one of the worst. With how important the transmission is it is understandable that a slipping transmission is dangerous. This often seems like it is popping out of gear. It is also accustomed with a high whine. If you have a manual and you learn your clutch is...
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...Our soybean oil press machine in line with the Ministry of Agriculture for agricultural technical conditions and standards, its processing and production of oil authentic, pure fidelity, is to create the best choice for the modern oil press machine. Our soybean oil press machine has the follow features and advantages: Energy - the same lower production of electric power by 40%, with an average of 6 kilowatt-hour savings calculations, the production of electricity can save 30 RMB. Labor - labor savings equivalent to 60% yield, 1-2 people can organize production, day labor efficiency cost savings of about 40 million. Versatile – our soybean oil press machine can be used just not soybean, pressed peanut, sesame, rapeseed, soybean, sunflower, flax and other 20 kinds of oil crops. Three pressing, pressing the net once. Pure oil - vacuum filtration residue to protect the oil clean, sanitary and quarantine standards. Small footprint - only 10-20 meters oil mill will be able to meet production needs. Then we talk about how to maintain soybean oil press machine in correct way in the follow text. (1) soybean oil press work 50 hours per lubrication, gear box oil cup above shall not oil, extra virgin oil press screw shaft bearing adjustment screw should be adjusted within the screw hole once per shift butter filling is prohibited dry grinding. (2) Run-oil soybean oil press each site should prevent intrusion of dust and other impurities, soybean oil press need to check the quality...
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...Activity 1.1.3 Gears – FT Introduction You do not have to look far to see gears. You might not think of an object such as a computer as having a lot of moving parts, but the CD tray on your computer is likely controlled by gears. A traditional watch is full of gears. The watch has one source of power or input that must move multiple hands continuously and at different speeds. Some watches also keep track of the day of the month. This may be low-tech by today’s standards, but imagine the challenge of choosing just the right gears to keep a watch synchronized. In a watch the gears are used to manipulate rotational speed. Gears are also used in many applications to control torque and rotational direction. Equipment fischertechnik gears and support pieces Calculator Procedure In this activity you will learn about gear ratios and how they affect speed and torque within a system. You will also construct simple and compound gear systems. Functions of Gears Gears change the speed of rotation. Gears change the direction of rotation. Gears change torque values. Gear Ratios By joining together two or more gears of different sizes, both the speed and the torque are changed from the input gear to the output gear. The larger gear within a system will always move slower and have more torque than the smaller gear. Gear Ratio (GR) is a comparison between the driver gear, also called the input (connected to the power source), and the gear being driven, or the output. Below are...
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...Sr. No. System Most Common Field Failures Rigid Tractor Tipper 1 Transmission "1. Syncrocone Carbon Lining Worn Out 2. Gear Box Crash Engagment during 4th / 5th Gear 3. Gear Rear / Front Oil Seal Leakages 4. Followers Damaged / Fork Brass Pad Early Wear 5. Top Gear Slippage " "1. Syncrocone Carbon Lining Worn Out 2. Gear Box Crash Engagment during 4th / 5th Gear 3. Gear Rear / Front Oil Seal Leakages 4. 1st Gear Helical Teeth Damaged 5. Top Gear Slippage / Top Gear Teeth Damaged " "1. Crawler / 1st Gear Teeth Damaged / Early Pitting Observed 2. Hose Breakages between Gear box & Oil Cooler 3. Oil Leakages through Oil Seals 4. Gear box Mounting Bolts found Loose 5. Range Selection Shifting Problems 6. PTO Brg Broken / Damaged 7. PTO Failures " 2 Rear Axle "1. Rear Axle Crown wheel Pinion Teeth Damaged 2. Excessive Backlash 3. Rear Axle Shaft Breakage 4. Tail Pinion Oil Seal Leakages 5. Rear Hub Inner / Outer Bearing Pitting 6. Hub Play Excessive " "1. Rear Axle Crown wheel Pinion Teeth Damaged 2. Excessive Backlash 3. Rear Axle Shaft Breakage 4. Tail Pinion Oil Seal Leakages / Oil Leakages through Carrier Housing Gasket 5. Rear Hub Inner / Outer Bearing Pitting 6. Hub Play Excessive " "1. Rear Axle Crown wheel Pinion Teeth Damaged 2. Excessive Backlash 3. Rear Axle Shaft Breakage 4. Tail Pinion Oil Seal Leakages / Oil Leakages through Carrier Housing Gasket 5. Rear Hub Inner / Outer Bearing Pitting 6. Rear Tandem Axle Dom Plate...
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...Brunswick Exercise: ANALYTICS EXERCISE: An MRP Explosion – Brunswick Motors 1. Initially, assume that Phil wants to minimize his inventory requirements. Assume that each order will be only for what is required for a single period. Weeks 1 2 3 4 5 6 7 8 9 10 11 12 Quantity 15 5 7 10 15 20 10 8 2 16 Gear Box Requirements: Weeks 1 2 3 4 5 6 7 8 9 10 11 12 Gross Requirements 15 5 7 10 0 15 20 10 0 8 2 16 On Hand 17 7 0 Planned order Receipts 10 15 20 10 8 2 16 Net Requirements 10 15 20 10 8 2 16 Planned Order Release 10 15 20 10 8 2 16 Input Shaft requirements: Weeks 1 2 3 4 5 6 7 8 9 10 11 12 Gross Requirements 30 10 14 20 0 30 40 20 0 16 4 32 On Hand 40 32 18 0 Planned order Receipts 2 30 40 20 16 4 32 Net Requirements 2 30 40 20 16 4 32 Planned Order Release 2 30 40 20 16 4 32 Phil would like to consider the costs that his accountants are currently using for inventory carrying and setup for the gearbox and input shafts. These costs are as follows: Part Cost Gear Box Setup = $90/order Inventory carrying cost = $2/unit/week Input Shaft Setup = $45/order Inventory carrying cost = $1/unit/week Gear Box Setup Cost = 8 x 90 = $720 Inventory = 4 x 2 = $8 Total = $728 Input Shaft Setup Cost = 5 x 45 = $225 Inventory = 96 x 1 = $96 Total = $321 Total Cost = $1,049 Calculate a schedule using least-total-cost lot sizing. What are the savings with this new schedule...
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...computers, named from A to T and have multiple laser printers which are shared by all the computers. These are called as nodes, i.e.linking devices. It also has a TMS (Token Machine System). Connecting devices used are switches and routers.Switches are used because a hub has only 8 ports and if a system wants to connect more than 8 devices to a hub, a hub becomes inefficient. So a switch is used to connect a number of devices, which is then connected to one of the port of a hub, so that the rest of the ports of the hub remain free. DATA TRANSMISSION : The transmission of binary data across a link is accomplished in serial mode. Serial Data Transmission : In serial data transmission one bit follows another , so we need only one communication channel rather than ‘n’ to transmit data between two communicating devices. The advantage of serial data transmission is that with only one communication channel, serial transmission reduces the cost of transmission over parallel by roughly a factor of ‘n’. In serial mode, one bit is sent with each clock pulse. Topology used In this centre, a star topology is used. Because, itis less expensive, requires less cabeling and easyto install and reconfigure. STAR TOPOLOGY : In a star topology, each device has a dedicated point to point link only to a central controller , usually called a‘hub’. The devices are not directly linked to each other. A star topology does not allow direct traffic between devices. The controller acts as an exchange. If one...
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...Name: _Aaron Hancock_ Date: _12OCT2014_ ISSC340 Week 1 Assignment (3% of Grade) APUS/Sanford Lesson 1 Review: Overview of Local Area Networks The purpose of this activity is to reinforce what you have learned so far about local area networks technologies. 1. What are the main architectural components of a LAN? (Minimum word count: 60) The main architectural components are 1: The network's physical topography (how the nodes are connected) 2: The access method (how the nodes access the transmission medium) 3: the transmission technique (how information passes through the network) 4: the transmission media (wired or wireless) 5: the use of specific protocols (the language used to communicate between computers) 6: the LAN's inter-connectivity (how the LAN shares with other networks) 2. Describe the function and characteristics of a network operating system (NOS). (Minimum word count: 100) A network operating system (NOS) manages the resources used within the network and enebles select services to select nodes. A NOS consists of two main components: a server component and a client component. The server component is the most complex component that runs on the server. The server component can do many things, to include; manage multiple users, provide access to files and printers, provide internet access, and enforce network security protocols. The client component runs on the client machine and enables the client to participate on the network. A NOS client component...
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...hypotactical graphs before I elaborate more. GRAPH 1) Typical gain from a 4-2-1 and a 4-1 compared to standard. Discussion here: https://www.facebook.com/note.php?note_id=292031897492759 **please don't ask me why only torque but power graph is not shown. **go google the relationship between power and torque A typical 4-2-1 makes good gain from low-mid rev range to rev cut, without loosing the low range. A typical 4-1 makes huge gain from mid rev range to cut, but loosing the low range slightly. SO WHICH IS BETTER? This is a question you should ask yourself. GRAPH 2) Typical revolution vs velocity relation for a 5-speed manual transmission check previous photo. discuss here: https://www.facebook.com/drexchan/posts/279650262057549 **revolution is RPM lah... **velocity is speed lor.... **applicable for automatic transmission too, don't ask. Now, check Graph 2, compare that to your driving style, see which rev range you use most (in normal driving, highway cruising, and sprint). Then compare that with Graph 1, see which type of extractor suits you. Situation A: You are doing a sprint, you will only use zone A (1k rpm to 3k rpm) once or twice and from 3rd gear on wards you will be using zone B (3k rpm to 6k rpm). So you want a 4-1 because it gains more in that range. Whatever gain in zone A (from a 4-2-1) is near to useless to you, and the gain in zone B from a typical 4-2-1 is lower than that from a typical 4-1. So a 4-1 is better for sprint. Situation...
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