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Glossary of Terms Coined by Michael Traum

All In-Head Valve Two Stroke
A two stroke engine (diesel, gasoline or both) that does not use cylinder ports. A two stroke engine with both the intake and the exhaust valves in the cylinder head. Along with a fully variable valve timing system the all in-head valve arrangement would allow the engine to run as either a four stroke or a two stroke, the main advantage of this being ease of starting without the use of a starting compressor.

Angled Cylindrical Roller Bearings
Roller bearings with cylindrical rollers that ride on angled races to provide thrust load carrying capability. Being cheap, easy to design and easy to use these have become the most popular bearings, but they are very inefficient for most applications. Since these are the dominant type of bearings they are simply known as roller bearings.

Axial Metering Collar and Rotational Metering Collar
The axial metering collar is a metering collar that slides along the axis of the plunger to uncover the fuel cutoff port in the plunger to end the injection event at the selected time. The rotational metering collar rotates around the plunger and has an angled slot cut into it to uncover the fuel cutoff port in the plunger at the selected end of injection timing value. Functionally both types of metering collars are the same except that a curved shape to the slot in the rotational metering collar could be used to modify the action of the governor mechanism where the axial metering collar responds only linearly to the action of the governor mechanism.

Capacitive Voltage Conversion
Charging capacitors in series and discharging them in parallel to convert electrical power to a lower voltage or charging capacitors in parallel and discharging them in series to convert electrical power to a higher voltage. Voltage conversion without the use of a transformer.

Crankshaft Wiggle Advance
The all at once advancing effect observed at some engine speed on a single cylinder gasoline engine with the points ridding directly on the crankshaft.

Dual Sheet Mid-Boom Sheeting
Sheeting a mainsail with two sheet tackles out to both rails. With the dual sheeting points somewhat forward the boom can be better controlled and shock loads associated with crash jibes can be prevented.

Electric Motor Driven Starting Compressor
An electric motor driven compressor (most likely of the centrifical type) used for starting a two stroke engine. The same compressor might also be used to supply operational boost at low engine speeds, but this type of engine would most likely also be turbocharged. A possible further sophistication might be the use of an exhaust gas turbine driven electrical generator to increase the flexibility and efficiency of co-generation over a wide range of engine speeds and loads.

Fixed Crankshaft Engine
An internal combustion piston engine where the crankshaft is stationary and the cylinder assembly rotates to provide the reciprocating motion relative to the pistons. The advantage of a fixed crankshaft engine is that reciprocating losses are essentially non-existent because the pistons and rods swing around the rod bearings in a circular motion instead of moving back and forth.

Flame Front Travel Speed of Fuel
The linear rate of flame front travel progression for a stochiometric air fuel ratio at some fixed compression pressure and temperature. Flame front travel speeds vary with air fuel mixture ratios and compression pressures and temperatures, but a single number would mostly be sufficient to describe the flame front travel speed of a particular fuel.

Frame to Frame Video Compression
Compressing digital video into much smaller file sizes than would be possible with vector compression of the individual images alone without sacrificing smoothness or image quality. The basic idea of frame to frame compression is that portions of the image that do not change from one frame to the next to not need to be stored over again, so the data rate of the video can be substantially reduced with the same high image quality and the same 60Hz standard frame rate.

Full Compression Ignition
Compression ignition occurring before top dead center. Compression ignition before the spark plug fires. This destructive early compression ignition instantly damages or destroys most engines, although full compression ignition engines that run at extremely high engines speeds of more than about 14,000RPM have been built.

Full Flame Front Travel Mode
When a gasoline engine is running without late compression ignition taking place. All of the fuel that combusts is burned by the passage of a flame front through the combustion chamber.

Late Compression Ignition
Compression ignition occurring after top dead center. Compression ignition occurring after a period of flame front travel combustion has raised the temperature and pressure in the combustion chamber to the point where compression ignition can occur. In a poorly running gasoline engine late compression ignition may occur slightly before top dead center, but this is to be avoided. In a high speed diesel engine initial combustion may occur somewhat before top dead center, but there is a considerable delay before the temperature and pressure rise significantly because the injected oil must mix with the air before it can fully combust.

Linear Electric Motor
An electric motor that does not rotate, but rather drives in a single direction or back and forth. A linear electric motor is different than a solenoid in that the linear electric motor has multiple windings fired sequentially to more efficiently provide large driving forces over a longer distance of travel.

Maximum Temperature of Combustion Potential of Fuel
The temperature of combustion where a particular fuel is theoretically capable of doing the most work. Not to be confused with the maximum attainable flame temperature which is often considerably higher and usually totally irrelevant to the amount of work that can be done by the fuel.

Metering Collar Emulator
An electronically controlled valve on the high pressure circuit of an injection system which opens under pressure but does not close under pressure. A metering collar emulator directly takes the place of a mechanically controlled metering collar and is functionally the same as a metering collar except that electronic control is mechanically simpler and normally allows somewhat better control of the quantity of fuel delivered than a mechanical governor.

Neutral Carving
Carving turns on a dirt bike with little or no power applied and no brakes applied. Neutral carving heavily loads the front tire, and bending a bit too hard can cause the front end to "wash out". Even though neutral carving is not quite as fast as power carving it is the preferred cornering technique for most types of racing because it is flexible and reliable.

Non-Reactive Additive
An additive used to modify the combustion properties of a fuel without chemically changing the base fuel. An additive that does not chemically react with the gasoline it is mixed with and does not catalyze any chemical reactions that change the gasoline it is mixed with.

Parallel Cylindrical Roller Bearings
Roller bearings with cylindrical rollers ridding on races parallel to the axis of rotation of the bearing assembly. These are very efficient bearings that can handle enormous loads, but they have no capability to handle thrust loads. Somewhat strangely this entire class of bearings are usually referred to as needle bearings.

Power Carving
Carving turns on a dirt bike under power with most or all of the weight on the rear tire. Power carving is the absolute fastest way around a turn, but is not always appropriate because it requires commitment to the maneuver and leaves little room for mid turn corrections.

Reciprocating Losses
Power wasted in throwing the pistons and rods back and forth in a reciprocating piston engine. Reciprocating losses in an engine are considerably less than would be expected just based on the weight of the pistons and rods, the stroke of the engine and the speed at which the engine is operating because a portion of the energy required to accelerate the pistons and rods is later able to drive the crankshaft forward as the piston slows towards top dead center or bottom dead center. Reciprocating losses tend to be directly proportional to the weight of the pistons and rods and tend also to be proportional to the cube of the mean piston speed. Double the weight of the pistons and rods and the reciprocating losses are about twice as high. Double the mean piston speed and the reciprocating losses are about eight times as high. Reciprocating losses due to the weight of the large end of the connecting rod are proportional not to the cube of the stroke of the engine, but rather are proportional to the cube of the diameter of the big end of the rod. This is why big (long stroke) normally aspirated gasoline engines work best with small rod journal diameters.

Tapered Roller Bearings
This is a hypothetical bearing type that may not have ever been built. Tapered rollers ridding on angled races allow the high load carrying capability and high thrust load handling ability of angled cylindrical roller bearings with the efficiency of ball bearings and parallel roller bearings. Because the tapered rollers tend to be "squished" out from between the races a system of ball bearings on the end of each tapered roller would be required. The complexity of this system of ball bearings and a race holder is the reason that this type of bearing has seen little or no use over the entire history of industry and transportation (or maybe nobody else ever thought of it, but that is doubtful).

Temperature and Pressure Requirement for Compression Ignition
The line (actually a non-linear function) of temperature and pressure combinations where compression ignition first takes place. For combustion engines it is usually a rather short segment of this line that is significant, and for most purposes this property of fuel could be expressed by a single number. This is the octane rating of the fuel, but the octane rating is such a poorly defined and widely misunderstood term that it can be very misleading. The octane rating is often mistakenly considered to take the flame front travel speed of the fuel into consideration.

Tensile Zone Analysis
A simplified form of structural analysis of a bending loaded structural member where the entire tensile load is assumed to be taken by an arbitrary uniform portion of the cross section of the structural member located near the outside edge of that structural member. The bending moment that a structural member can sustain is then assumed to be the cross sectional area of this tensile zone multiplied by the tensile strength of the material multiplied by the length of a lever arm from the centroid of the tensile zone to an arbitrary pivot point on the compression side of the structural member.

Three Clutch Hybrid Drive
The use of three clutches on a combustion engine and an electric motor to provide flexibility in how and when each device is used. One clutch is on the motor and one clutch is on the engine with the third clutch on the output allowing any one of four different combinations of use of the engine and/or motor/generator. The main application of this three clutch drive system would be on electric drive boats, but some land vehicles such as small tractors and utility vehicles might also benefit from the same engine, motor and battery system being able to be used for efficient high output electrical generation. In most applications the electric motor would have it's own reduction gear before the clutch. Likewise in most applications another reduction gear or selectable ratio transmission would be located after the output clutch, but a reversing gear normaly would not be required.

Three Stage Electrical Generator
An electrical generating device or system with a large permanent magnet generator on a clutch as well as a small permanent magnet generator that spins all the time and a medium size field winding type alternator that spins all the time. The purpose of this three stage system would be to be able to efficiently provide for a wide range of electrical loads as well as to provide smooth operation under rapidly changing loads. Sophisticated control circuitry could run the large permanent magnet generator up to speed as an electric motor before engaging the clutch which would allow the clutch to be smaller and more efficient without wearing out. The always spinning medium size field winding type alternator would be required to provide instantly available medium to medium high power output for rapidly changing or very short duration loads as well as to augment the output of the small permanent magnet generator for supporting light loads.

Time of Combustion Injection
Injection of fuel after compression ignition has already taken place. Not to be confused with injection of fuel during flame front travel combustion, which although somewhat useful is not true time of combustion injection. In a diesel engine all of the fuel is injected with time of combustion injection.

Two Into Three Interpolator
A digital camera that interpolates the sensor output up to higher resolution than the native resolution of the sensor. The standard amount of interpolation on (nearly) all digital cameras is for each two lines of horizontal resolution to be interpolated up to three lines of horizontal resolution in the output file and for each two lines of vertical resolution to be interpolated up to three lines of vertical resolution in the output file. This two into three interpolation results in an output file that has a 225% higher pixel count than the native resolution of the sensor.

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