A process and an apparatus for sinking drill holes, in particular exploration and extraction drill holes, with a drill pipe, which at its end facing the floor to be mined is provided with a guide point fixed in the longitudinal direction of the drill pipe and a drill head with at least one cutting element. The drill head can be moved in the longitudinal direction of the drill pipe between a top position, in which the guide point projects beyond the at least one cutting element, and a bottom position in which the at least one cutting element is positioned at the same height as the end of the guide point or projects beyond same in the operating direction. When the drill head is in the top position, the drill pipe is moved in the direction of the drill hole to be produced until the guide point by cooperating with the floor fixes it in position. Then the drill head is moved into its bottom position in order to produce the drill hole.

The invention relates to a process and an apparatus for sinking drill holes, in particular for exploration and extraction and drill holes.
Exploration drill holes are made for the purpose of prospecting deposits and should permit the taking of samples of the material present in the deposit. Exploration drill holes are sunk, in particular, when the deposit is located at great depth and/or when water that is present above the deposit, e.g. an ocean or sea, does not permit the sinking of exploration shafts.
Extraction drill holes serve to extract the deposit content from bottom layers. An example of extraction drill holes is the mining of marine sediments with diamond inclusions present on the ocean floor.
The deposits containing the diamonds have generally been formed in front of river mouths in the form of not very thick layers spread out on a rock base. To mine the diamond-containing sediment material, apparatuses are used which are lowered onto the ocean floor from ships on an extendible drill-pipe. Such apparatuses may have drill heads which are designed for drill holes with a large diameter. Several such drill holes are made close to one another so as to be able to extract as much as possible of the diamond containing material.
When the drill head fastened to a drill-pipe which may have a great length encounters the ocean floor, the problem occurs that at the place on the ocean floor where the drill hole is to be made, the drill head of the drilling tool does not penetrate immediately, but tends to slip and move around spiral-shaped in a circle, especially when the ocean floor has even the slightest slope.
To prevent this slipping sideways of the drill head, it is already known to arrange a centering guide point underneath the drill head, which under the drilling force exerted in the operating direction of the drill head penetrates into the surface of the sediment layer and, in particular in the initial phase of the drilling, provides a guidance that prevents a slipping sideways of the drill head at the start of the drilling operation, i.e. when the drill head is not yet guided at is sides by the drill hole walls.
When the drill head has passed nearly completely through the sediment layer, the projecting guide point is the first to encounter the generally rocky base located underneath, into which it cannot penetrate or only very slowly and with great wear. The drill head than cannot penetrate further into the sediment layer.
As the profitability of the extraction process depends on the quick sinking of a large number of adjacent drill holes, the respective drilling operation until now is greatly delayed when the guide point encounters the bedrock located underneath the sediment, and accordingly becomes uneconomical.
From the U.S. Pat. No. 3,277,972 an apparatus is known with which the drill head is moved down during the penetrating into a soft sediment layer. The drill head is arranged movable in the drill-pipe direction relative to the housing, so that it can be moved down separately from the housing as soon as the front end of the housing encounters a layer of hard rock.
From the AT-PS 379 863 a drill-pipe is known, which for the guiding in the drill hole comprises a guide sleeve that partly radially surrounds the drill-pipe, the outside diameter of which guide sleeve corresponds approximately to that of the advancing drill head.
It is the objective of the invention to develop further a process and an apparatus for sinking drill holes, in particular exploration and extraction drill holes, of the described type in such a way that a deposit can mined through less hard rock layers up to the generally rocky primary rock located underneath, without in this case the process becoming uneconomical. Furthermore the apparatus should stand out by an adaptability to the most varying drilling conditions and depths and require the lowest possible production costs.
This problem associated with the process is solved by the subject of claim 1.
According to the invention, a drill-pipe which at its end facing the floor to be mined is provided with a guide point fixed in the longitudinal direction of the drill pipe, is lowered to the place where the drill hole is to be made. When doing so, normally the guide point will penetrate at least slightly into the sediment layer. Next a drill head, which on its side facing the floor has at least on cutting element that can be moved in the longitudinal direction of the drill pipe between a top position, in which the guide point projects beyond the at least one cutting element, and a bottom position in which the at least one cutting element is positioned at the same height as the end of the guide point or projects beyond same in the operating direction, is moved from its top position assumed during the lowering of the drill pipe into its bottom position. Seeing that the guide point has penetrated by a certain amount into the sediment layer, the at least one cutting element of the drill head produces in the sediment layer a drill hole start which will guide the drill head laterally before the guide point assumes a decreasing laterally guiding effect of the drill head. When the drill head penetrates further into the sediment layer, the at least one cutting element is, therefore, positioned on the same plane as the end of the guide point or even moves ahead of same, so that according to the invention drill holes up to the bedrock located underneath the sediment layer can be made without any problems. Seeing that as a rule during the drilling operation the guide point need not penetrate into the rock layer located underneath the sediment layer, its wear is reduced considerably.
With a first variant of the process according to the invention, during the drilling operation the drill pipe is made to rotate around its longitudinal axis and as a result thereof, both the drill head fixed rotationally rigid to the drill pipe and also the guide point fixed rotationally rigid to the drill pipe and also the guide point fixed rotationally rigid to the drill pipe, are made to rotate. With this variant of the process, therefor, a xe2x80x9cdrillingxe2x80x9d of the guide point into the sediment layer takes place.
It may, however, also be advantageous, to drive the drill pipe and to transmit the turning momentum to the rotationally fixed drill head, but not to the guide point which is mounted rotating around the longitudinal axis of the drill pipe. This ensures that the guide point does not rotate in the sediment. It is true that as a result thereof no drilling of the guide point into the sediment layer takes place, but it was found that in many cases an adequate guiding function of the guide point is obtained when it is pushed over a short length into the sediment layer exclusively by the mass bearing on it. As no relative movement takes place between the sediment layer and the guide point, the guide point is subjected to less wear compared to the aforementioned variant of the process according to the invention.
Particularly advantageous is the further development of the process with which the drill pipe is mounted rotationally rigid and the drill head is made to rotate relative to the longitudinal axis of the drill pipe, as by this measure the drive unit normally provided on the side of the drill pipe opposite the drill head side as well as possible complicated rotary transmission lead-throughs can be dispensed with. In this case it is possible to arrange the guide point rotationally rigid on the drill pipe.
However, in the case of a relatively hard sediment layer it may be advantageous to arrange the guide point rotating around the longitudinal axis of the drill pipe and to make it rotate around it longitudinal axis together with the drill head, as this permits a xe2x80x9cdrillingxe2x80x9d of the guide point into the sediment layer in order to increase the initial guiding effect.
In another, particularly preferred variant of the process the guide point is again mounted rotating around the longitudinal axis of the drill pipe, but is only taken along by the drill head when the latter, coming from its top position, assumes a position in which the at least one cutting element of the drill head has at least approximately reached the height of the end of the guide point.
This measure ensures that the guide point, as long as it ensures the guiding of the drill head and cannot penetrate further into the sediment layer, is not subjected to wear caused by an idle rotating in the sediment layer, but when the drill head penetrates deeper into the sediment layer it reliable prevents the formation of a xe2x80x9ccorexe2x80x9d in the area not covered by the at least one cutting element.
With a particularly preferred embodiment of the process the force with which the front end of the drill head rests against the floor to be mined or the drill hole bottom, can be adjusted by at least one buoyancy body provided on the drill head.
The design problem is solved by the apparatus disclosed in claim 8 in that on the end of the drill pipe facing the floor to be mined or the front end of the drill hole, a guide point fixed in the longitudinal direction of same is fastened, and that the drill head can be moved in the longitudinal direction of the drill pipe between a top position, in which the guide point projects beyond the at least one cutting element, and a bottom position in which the at least one cutting element is positioned at the same height as the end of the guide point or projects beyond same in the operating direction of the drill head. With the apparatus according to the invention the guide point, therefore, in the first instance serves to prevent a moving sideways of the drill head when starting the drilling, whereas after the drill head has been lowered relative to the drill pipe to behind the plane defined by the at least one cutting element, it lags behind and cannot obstruct the drilling operation by impacting on a rock base or rocky inclusions as caused by a moving ahead.
With the apparatus according to the invention it is possible to make the drill head rotate in the known manner in that the one end of the drill pipe is mounted rotating around its longitudinal axis and the use of a power-driven rotary head, which in the area of this end cooperate with the drill pipe, is provided. In this case the drill head must be arranged rotationally rigid on the drill pipe.
As in many cases, to guide the drill head it will suffice when at the beginning of the drilling operation the guide point is just pushed into the sediment layer, to reduce the wear of the guide point it may be advantageous to mount it on the drill pipe rotating around the longitudinal axis of same.
However, it is particularly advantageous when the end of the drill pipe facing away from the drill head it mounted rotationally rigid on the installation for mounting the drill pipe.
Particularly suitable for such a mounting is a cardanic suspension.
In this case the drill head is preferably made to rotate relative to the drill pipe around the longitudinal axis of the latter by means of a drive unit provided for same.
The drive unit advantageously comprises a rotary motor which cooperates with a device arranged on the drill pipe for receiving a turning momentum, which is provided preferable in the form of longitudinal teething.
The rotary motor may be a hydraulic motor.
However, it is also possible to use an electric motor as the rotary motor.
Tests have shown that in certain sediment layers the guiding effect of the guide point is sufficient when, without it rotating around its longitudinal axis, it is just pushed into the sediment layer, but other sediment layers require a rotating of the guide point around it longitudinal axis. It, therefore, is advantageous, to mount the guide point on the drill pipe rotating around the longitudinal axis of same and to provide on the guide point entrainers which can be made to engage with counter-entrainers provided on the drill head.
Preferably the entrainers and counter-entrainers consist, in the case of the entraining of the guide point, of longitudinal teeth that engage into one another.
It was found, however, that for sediment layers an embodiment of the apparatus is very suitable, with which the entrainers and counter-entrainers engage independent of the position of the drill head, related to the longitudinal direction of the drill pipe.
Particularly suitable for other sediment layers, however, is an apparatus where the entrainers and/or the counter-entrainers are designed in such a way that the guide point is only engaged with the rotating drill head when the at least one cutting element is positioned at the same height as the end of the guide point or projects beyond same in the operating direction of the drill head. This measure ensures that a further lowering of the drill head into the sediment layer is not prevented by a xe2x80x9ccorexe2x80x9d formed in the area not covered by the at least one cutting too.
In a preferred embodiment the longitudinal teething forming the entrainers and counter-entrainers is provided only on the bottom part of the guide point, the counter-teething only in the upper part of the drill head, in such a way that when the drill head is moved along the drill pipe in the direction of the guide point, the upper end of the teething engages with the bottom and of the counter-teething when the at one cutting element has nearly reached the height of the end with the guidepoint.
A particularly good adaptability of the apparatus to different sediment layers is obtained when at least one buoyancy body is provided on the drill head for adjusting the drilling force acting in the operating direction of the drill head. By this measure the drilling force acting in the operating direction of the drill head can adapted to the properties of the sediment layer in question, without causing a change in the force with which the guide point is pushed against the sediment layer. Thus it is possible, in particular in the case of very hard sediment layers, to press the guide point into the layer with great force so as to achieve an adequate guiding effect, but at the same time to regulate the drilling force in such a way that the engaging of the at least one cutting element does not cause a slipping sideways of the drill hole, whereas on the other hand an optimum drilling progress is achieved.
When the at least one buoyancy body comprises a tank which optionally can flooded or filled with a gas, preferable compressed air, then the drilling force can also be changed during the drilling operation. As a result it is possible, for example, to choose at the beginning of the drilling operationxe2x80x94as long as there still exists the risk of a xe2x80x9cdriftingxe2x80x9d of the drill holexe2x80x94a lower drilling force, but to increase the drilling force so as to increase the drilling progress as soon as the drilling tool begins to guide itself in the drill hole.
The apparatus according to the invention is preferably used in conjunction with a floating platform for sinking drill holes in the ocean floor, on which platform the end of the drill pipe opposite the drill head end is mounted.
In that case it is particularly advantageous, in order to compensate vertical movements of the platform caused by the ocean swell or tide lift, to split the drill pipe into an upper drill pipe part mounted on the platform and a bottom drill pipe part on which the drill head and the guide point are mounted, wherein the upper and the bottom drill pipe parts engage into one another telescopically in the longitudinal direction of the drill pipe and can be moved relative to one another in such a way that the vertical movement of the platform are compensated without the drilling force experiencing a significant change.
With a preferred embodiment of the apparatus according to the invention, a length-variable force generator, preferably a piston/cylinder unit is provided which is mounted on the one side on the bottom drill pipe part, on the other side on the drill head and with which the length variation takes place in the direction of the longitudinal axis of the drill pipe. By this measure the drill head can be moved relative to the bottom part of the drill pipe without this requiring an activation of the winch provided on the platform and a stressing of the ropes. This is especially advantageous when the drill head is xe2x80x9cjammedxe2x80x9d in the drill hole, e.g. due to a collapsing of the drill hole walls, seeing that by a corresponding activating of the length-variable force generator the drill head can be moved upwards relative to the guide point which, especially when the drill hole extends through the entire sediment layer, rests on the hard bedrock located underneath. In most cases the drill head can, therefore, also be loosened after a collapsing of the drill hole walls.
This embodiment furthermore makes it possible to adapt the projecting length of the guide point to the conditions corresponding to the properties of the floor.
If on the bottom drill pipe part, preferably near its upper end, at least one buoyancy body is provided, the buoyancy force of which can be controlled, then the force with which the guide point rests on the floor can be adapted to the prevailing conditions. If in this case the drill head is provided with a length-variable force generator, then the drilling force can be increased by the proportionate mass force of the bottom drill pipe part and of the components attached thereto in the axial direction.

Method and device for driving bore-holes, especially in the sea bed, using a guide tip

Wirth Maschinen-Und Bohrgeraete Fabrik GmbH


A process is provided for preparing a spent noble metal fixed-bed catalyst for precious metals recovery, comprising: a) adding the catalyst to a caustic solution to wash the spent catalyst and to make a wash slurry having an alkaline pH, wherein the spent catalyst has been in contact with chloroaluminate ionic liquid catalyst, and wherein the spent catalyst comprises from 5 to 35 wt % chloride; and b) filtering the wash slurry and collecting: i) a filter cake having from at least 70 wt % of the chloride in the spent catalyst removed and having the noble metals retained, and ii) a wash filtrate. Also provided is a filter cake comprising a washed consolidated cake having 40 to 75 wt % solids, a cake moisture content from 25 to less than 60 wt %, 0.1 to 1.5 wt % total noble metals, and a residual chloride content of from zero to less than 4 wt %.

Improved processes for removal of expended ionic liquid and elevated chloride levels from spent catalyst extrudates are needed, as a precursor to precious metals recovery. Traditional means of preparing spent noble metal fixed-bed catalysts are not optimized for those spent noble metal fixed-bed catalysts that have been in contact with chloroaluminate ionic liquid catalysts. A new process is needed to reduce chloride content and retain the noble metals in the spent catalyst.

Process for preparing a spent catalyst for precious metals recovery


A print medium that is expandable and collapsible comprises two sheets separated by at least one collapsible brace. The collapsible brace includes a first wall attached to one of the sheets and a second wall that swings in relation to the first wall. The swinging motion of the second wall in one direction expands a distance between the two sheets, while a swinging motion of the second wall in the opposite direction collapses the distance between the two sheets. At least one sheet of the paper may include an ink receiving layer. When the collapsible brace is expanded, the print medium becomes a substantially rigid structure.

Technological advances in computer printer technologies have made computer printers less expensive and thus, widely available to all computer users. Currently available printers are able to produce full-color and highly detailed images. Digital cameras have also become widespread and are often used in place of conventional cameras due to their versatility and functionality. For example, images obtained with digital cameras are easily downloadable to a computer where a user is able to collect and manipulate the various images and print them out using the high quality printers of today.
The images and documents created on the printers are often printed on a printing medium, such as a piece of paper. However, standard printer paper is typically non-rigid. To make the printed information more sturdy and suitable for visual display, the printed paper is usually attached to a backing or other rigid support structure. However, attaching the printed paper to the backing is time consuming and requires use of additional materials.
One such type of backing that is used is construction paper. Construction paper is typically a thick, rigid paper of varying colors that is often used in the craft industry. Another type of backing that may be used to make a print medium rigid is corrugated paperboard or cardboard. Cardboard is typically made with three layers of paper stock, where a middle corrugated layer is sandwiched between two flat paper layers. The middle layer is corrugated by forming the middle layer in a pattern of alternating ridges and grooves, with the peaks and troughs of the ridges and grooves being attached to the interior surfaces of the two flat paper layers, typically with an adhesive.
In addition to making the printed information rigid, the backing may be bent or folded into various shapes for the creation of decorative objects. Possible uses for the backings include forming a curved media in the shape of a rigid cylinder for displaying advertisements on a restaurant table, incorporating the backing into various craft projects or figures to produce decorations for holidays and parties, or making protective and insulating gift packages. However, since printers and copiers are limited to the thickness of printing medium that the printer or copier may accept for printing, passage of a cardboard or construction paper backing through the printer may be problematic since most printers require a print medium having a caliper thickness of 0.040 inches or less.
U.S. Pat. No. 6,139,938 to Lingle et al. discloses a printable, corrugated paperboard. The paperboard in Lingle et al. is constructed from three layers of paper having a middle corrugated layer that is sandwiched between two outside layers. The paperboard has a combined thickness of less than 0.042 inches allowing the paperboard to pass through a printer. However, the corrugated layer in the paperboard of Lingle et al. is glued to the outside layers, has a set thickness, is not expandable to a greater thickness and is not collapsible.
In view of the foregoing, there is a need in the art for a paper or printer medium that is thin enough in a collapsed state to have an image disposed thereon and pass through a typical printer, and which may be subsequently transformed to a rigid, sturdy structure for use in creating objects displaying the information printed on the paper or printer medium.

Hewlett-Packard Development Company, L.P.


The present invention provides a set of electrode plates for rolled electrochemical component and a cell comprising it. The set of electrode plates comprises a stripe-shaped first electrode plate, a stripe-shaped second electrode plate and a stripe-shaped separator, said separator being positioned between the first electrode plate and the second electrode plate, and these three being revolved into a roll in the length direction, wherein said first electrode plate comprising a stripe-shaped first collector and the active material coated on the surface of said first collector, said second electrode plate comprising a stripe-shaped second collector and the active material coated on the surface of said second collector, a first exposed portion with a predetermined width on which the active material are not coated being formed on at least one of two terminals in a width direction of the first electrode plate to constitute a first collecting section, a second exposed portion with a predetermined width on which the active material are not coated being formed on at least one of two terminals in a width direction of the second electrode plate to constitute a second collecting section, a structure for preventing sharp crippling is formed on at least one of said first collecting section and said second collecting section in at least the innermost periphery of the set of electrode plates. Hence, a high quality component having reliable and stable electrical connection between the collecting section and the collecting plate thereof and prevented from inner short-circuit in the set of roll-shaped electrode plates can be obtained.

The rolled electrochemical components are widely used in batteries, double-charge-layered capacitors and like. Generally, this component has a set of electrode plates which is revolved into a roll and provided with a stripe-shaped separator disposed between a positive electrode plate which is coated with active material on its stripe-shaped collector and a negative electrode plate which is coated with active material on its stripe-shaped collector. The set of electrode plates together with electrolyte is accommodated in a metal casing and protrudes from the collector of the electrode plate of the positive or negative electrode on both upper and lower end faces or one end face of said set of electrode plates. A collecting plate is typically welded on the top end of the collector.
In the past, a structure was presented, in which a collecting section had a thin metal plate welded and in which the thickness is increased. On an end section of the collector, splits (in the description, "split" means that a collector is only cut resulting in a split which has essentially no width or separation; the "notch" means that a collector is partly cut off and a notch is formed which has a broad width) are formed on the collecting section, and a collecting plate is welded on the collecting section with the notches. Therefore, compared with the cell in which the collector is directly welded to the collecting plate without the thin metal plate welded on its end section, the collecting section will not be damaged and not be bent to such an extent that the separator would be punched or pricked through (i.e., having a hole formed therein) even though the collecting section is strongly pressed through the collecting plate, so that the possibility of an inner short-circuit can be reduced, and the electrical connection between the collecting section and the collecting plate can be stabilized (see, Japanese Patent Published No. 2000-77054).
For the foregoing collection structure of the prior art, however, a thin metal plate is welded on an end section of a collector to form a collecting section with splits formed in an equally-spaced manner, so that there is a problem that the collecting section positioned in the innermost periphery of the set of electrode plate with the smallest radius of curvature which are revolved into a roll can not have a smooth arc-shape but a sharp crimping or crippling, so that the separator may be punched through, thereby the inner short-circuit may occur.
The present invention is directed to solve the foregoing technical problem in prior art. The object of the invention is to provide a set of electrode plates for rolled electrochemical components and cells comprising such components, in which there is reliable and stable electrical connection between the collecting section and the collecting plate in the cell and the inner short-circuit may be avoided in the set.
Hence, with the rolled electrochemical component of the present invention, a high quality component having reliable and stable electrical connection between the collecting section and the collecting plate thereof is provided, which prevents an inner short-circuit in the set of roll-shaped electrode plates.

Set of electrode plates for rolled electrochemical component and a cell comprising such electrode plates


A bonding arm swinging type bonding apparatus that has a rotational center 13 of the bonding arm 1 beneath the bonding arm. The rotating shaft parts 11 of circular arc form rotary motors 10 that rotate about the rotational center 13 of the bonding arm 1 are attached to the bonding arm 1, and the rotating shaft parts 21 of circular arc form air bearings 20 that rotate about this rotational center 13 are provided so that the rotating shaft parts of the circular arc form air bearings 20 are rotatable as a unit with the rotating shaft parts 11 of the rotary motors 10.

1. Technical Field
The present invention relates to a bonding arm swinging type bonding apparatus in which the swinging center of the bonding arm during bonding can be set on a bonding surface.
2. Description of the Related Art
Japanese Patent Application Laid-Open (Kokai) No. 2003-347349, for instance, discloses an example of a bonding arm swinging type bonding apparatus. In this bonding arm swinging type bonding apparatus, the bonding head is provided so that it can be maintained in a position that is higher than the work plane and so that the bonding arm need not be lengthened even in cases where the bonding area is broad. Thus, in this bonding apparatus, a high-speed operation can be performed while suppressing any increase in the inertia of the bonding arm.
More specifically, the above-described prior art bonding apparatus comprises a bonding arm which has a capillary attached to a tip end thereof, a driving motor which is attached to the rear end portion of this bonding arm in order to drive the bonding arm, and a bonding head in which a circular arc form window structure is formed so that the window supports supporting portions that are disposed on both sides of the bonding arm. The center of the circular arc of the window is disposed on the plane of the bonding surface, and the supporting portions of the bonding arm move along the circular arc shape in the circular arc form window of the bonding head.
In the above-described prior art, a bonding arm that is short in length can be used. Accordingly, this bonding apparatus can reduce the inertial moment of the bonding arm. However, since the driving motor is installed on the rear end portion of the bonding arm, which is apart from the rotational center of the bonding arm, there are limitations to the reduction in the inertial moment that can be achieved.

Bonding arm swinging type bonding apparatus


A progressive displaying terminal and a video playing method and an image processing apparatus thereof are provided. The video playing method includes: extracting an odd field and an even field of each frame of an interlaced video, where the interlaced video has an initial resolution higher than a screen resolution of a progressive displaying terminal, and scaling the odd field and the even field of each frame respectively and then playing the odd field and the even field of each frame. In this way, the present disclosure eliminates the need of de-interlacing when playing an interlaced video on a progressive displaying terminal, so the hardware configuration requirements and the cost are reduced and a good picture quality is ensured during playing of the video.

Currently, when a progressive displaying terminal plays an interlaced video, generally a de-interlacing (DI) operation is required to make an improvement on or eliminate the "jaggies". However, the de-interlacing operation imposes high requirements on hardware configuration of the progressive displaying terminal, and particularly for high-definition interlaced videos having a resolution of 1920*1080 and displaying 25 frames per second, the processing burden in the interlaced processing is 1920*1080*25 per second, and such a huge processing burden imposes higher requirements on the hardware configuration. This leads to a high cost and makes it difficult to guarantee a good picture quality in video playing.

Progressive displaying terminal and video playing method and image processing apparatus thereof


A brake control system and method having variable braking modes includes an operation part, a brake input detector, and a controller. The operation part is disposed to allow a driver to selectively input one of a plurality of predetermined braking characteristics modes. The brake input detector detects a brake pedal operation variance or a brake pedal manipulation force of the driver. The controller receives a mode selection signal from the operation part to recognize a braking characteristic mode selected by the driver, and then controls a wheel brake to generate a predetermined pattern of braking force in the braking characteristic mode selected by the driver based on the brake pedal operation variance and the brake pedal operation force detected by the brake input detector.

Generally, a brake of a vehicle decelerates or stops the vehicle in operation, or maintains the vehicle at a standstill. When the brake operates, kinetic energy of the vehicle is converted into thermal energy by mechanical friction, and frictional heat is emitted therefrom to the atmosphere.
Vehicle brakes are divided into a drum-type hydraulic brake and a disc-type hydraulic brake. In a disc-type hydraulic brake, a braking force is generated when a disc is rotating together with a wheel instead of a drum, and the brake is strongly pressed by a frictional pad.
However, since hydraulic brakes require mechanical components, hydraulic pipes, and components for controlling a hydraulic pressure connected to a brake pedal of a driver's seat, their structure is complicated.
Accordingly, Electro-Mechanical Brakes (EMBs) have been recently used to simplify the structure of the braking apparatus.
Unlike typical hydraulic brakes, EMBs refer to brakes that obtain a braking force by pressing a frictional pad using a mechanism driven by an electric motor.
Common EMBs have an actuator including a motor that rotates for braking or braking release and applies pressure to the frictional pad using the torque of the motor to allow the disc to be pressurized or rubbed by friction. The EMBs receive a braking intention of a driver through the brake pedal, and then control a braking pressure of a wheel using the motor.
Since the EMBs, as the next-generation braking concepts, have quick response speed and enable precise control compared to the hydraulic brakes, the EMBs are expected to be preferentially applied to eco-friendly vehicles such as electric vehicles.
EMBs can also be achieved in combination with hydraulic brakes. For example, a hydraulic brake and an EMB can be applied to the front wheel and the rear wheel, respectively. Compared to a system adopting only a hydraulic brake, the combination system of the EMB and the hydraulic brake has a simple structure and an excellent braking force response with an easy control of the braking force.
Also, a Brake-By-Wire (BBW) system in which EMBs brakes are mounted in both front and rear wheels can be implemented. The BBW system performs braking by allowing electric calipers disposed at the front and rear wheels to hold the disc according to signals of a controller.
An Electro-Hydraulic Brake (EHB) system is another form of the BBW system and is different from the EMB. In the EHB system, a controller receives signals from a pedal travel sensor and a hydraulic sensor in a master cylinder to detect a driver's brake intention and requests deceleration and controls the hydraulic pressure of an accumulator through a solenoid valve to perform hydraulic braking on wheels.
Since the BBW system delivers a driver's braking intention using electric signals, there is no mechanical connection between the brake pedal and the wheel, and independent and precise control of the braking force on each wheel of a vehicle is possible. Furthermore, control of the braking force is easy, braking distance can be shortened, and braking stability can be increased.
The BBW system uses a pedal simulator to provide a hydraulic pedal-like feeling using hysteresis characteristics. The pedal simulator achieves the feeling of a pedal such as an existing hydraulic brake when a driver operates a pedal and assists the braking operation of a driver by forming a pedal repulsive force against the braking operation.
The BBW system is more advanced than typical braking apparatuses in which the characteristics of driver's pedal effort (force applied to the pedal) vs. braking force shows a single mode.
For example, when a driver steps on the brake pedal by force A1, the pedal variance (pedal depth, pedal travel, and pedal stroke) by force A1 is substantially equal to A2. When the pedal variance is A2, the braking force of the braking apparatus substantially shows a predetermined value A3 according to the pedal variance.
When the pedal operation variance is constant, the constant braking force is always generated to satisfy driver request deceleration. The pedal stroke according to a specific pedal effort, and the driver request deceleration and braking force corresponding to the pedal stroke are determined in a specific single mode. Also, variation patterns of the braking force according to pedal effort and the pedal operation variance are determined in a single mode.
Thus, in the related art, since the characteristics of the braking feeling of a vehicle according to pedal effort are not changed in a pre-designed single mode, and pedal effort or braking force characteristics cannot be changed according to driver's tendencies, sufficient braking force may not be achieved by, for example, women or elderly men.
Also, it is difficult to provide a sporty braking feeling to a driver who tends to enjoy sports driving.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Brake control system and method having variable braking modes


An electrophoretic display comprises an electrophoretic medium having a plurality of charged particles suspended in a suspending fluid, and two electrodes disposed on opposed sides of the electrophoretic medium. At least one of the electrodes is light-transmissive and forming a viewing surface. The display has a closed optical state in which the charged particles are spread over substantially the entire viewing surface so that light cannot pass through the medium, and an open optical state in which the electrophoretic particles form chains extending between the electrodes so that light can pass through the electrophoretic medium. Insulating layers are disposed between the electrodes and the electrophoretic medium. Similarly electrophoretic displays are provided equipped with color filter arrays or reflectors.

This invention relates to electro-optic displays. These displays may either be shutter mode displays (as the term is defined below) or light modulators, that is to say to variable transmission windows, mirrors and similar devices designed to modulate the amount of light or other electromagnetic radiation passing therethrough; for convenience, the term "light" will normally be used herein, but this term should be understood in a broad sense to include electromagnetic radiation at non-visible wavelengths. For example, as mentioned below, the present invention may be applied to provide windows which can modulate infra-red radiation for controlling temperatures within buildings. More specifically, this invention relates to electro-optic displays and light modulators which use particle-based electrophoretic media to control light modulation.
Particle-based electrophoretic displays, in which a plurality of charged particles move through a suspending fluid under the influence of an electric field, have been the subject of intense research and development for a number of years. Such displays can have attributes of good brightness and contrast, wide viewing angles, state bistability, and low power consumption when compared with liquid crystal displays.
The terms "bistable" and "bistability" are used herein in their conventional meaning in the art to refer to displays comprising display elements having first and second display states differing in at least one optical property, and such that after any given element has been driven, by means of an addressing pulse of finite duration, to assume either its first or second display state, after the addressing pulse has terminated, that state will persist for at least several times, for example at least four times, the minimum duration of the addressing pulse required to change the state of the display element. It is shown in published U.S. Patent Application No. 2002/0180687 that some particle-based electrophoretic displays capable of gray scale are stable not only in their extreme black and white states but also in their intermediate gray states, and the same is true of some other types of electro-optic displays. This type of display is properly called "multi-stable" rather than bistable, although for convenience the term "bistable" may be used herein to cover both bistable and multi-stable displays.
Nevertheless, problems with the long-term image quality of these displays have prevented their widespread usage. For example, particles that make up electrophoretic displays tend to settle, resulting in inadequate service-life for these displays.
As noted above, electrophoretic media require the presence of a suspending fluid. In most prior art electrophoretic media, this suspending fluid is a liquid, but electrophoretic media can be produced using gaseous suspending fluids; see, for example, Kitamura, T., et al., "Electrical toner movement for electronic paper-like display", IDW Japan, 2001, Paper HCS1-1, and Yamaguchi, Y, et al., "Toner display using insulative particles charged triboelectrically", IDW Japan, 2001, Paper AMD4-4). See also European Patent Applications 1,429,178; 1,462,847; and 1,482,354; and International Applications WO 2004/090626; WO 2004/079442; WO 2004/077140; WO 2004/059379; WO 2004/055586; WO 2004/008239; WO 2004/006006; WO 2004/001498; WO 03/091799; and WO 03/088495. Such gas-based electrophoretic media appear to be susceptible to the same types of problems due to particle settling as liquid-based electrophoretic media, when the media are used in an orientation which permits such settling, for example in a sign where the medium is disposed in a vertical plane. Indeed, particle settling appears to be a more serious problem in gas-based electrophoretic media than in liquid-based ones, since the lower viscosity of gaseous suspending fluids as compared with liquid ones allows more rapid settling of the electrophoretic particles.
Numerous patents and applications assigned to or in the names of the Massachusetts Institute of Technology (MIT) and E Ink Corporation have recently been published describing encapsulated electrophoretic media. Such encapsulated media comprise numerous small capsules, each of which itself comprises an internal phase containing electrophoretically-mobile particles suspended in a liquid suspending medium, and a capsule wall surrounding the internal phase. Typically, the capsules are themselves held within a polymeric binder to form a coherent layer positioned between two electrodes. Encapsulated media of this type are described, for example, in U.S. Pat. Nos. 5,930,026; 5,961,804; 6,017,584; 6,067,185; 6,118,426; 6,120,588; 6,120,839; 6,124,851; 6,130,773; 6,130,774; 6,172,798; 6,177,921; 6,232,950; 6,249,271; 6,252,564; 6,262,706; 6,262,833; 6,300,932; 6,312,304; 6,312,971; 6,323,989; 6,327,072; 6,376,828; 6,377,387; 6,392,785; 6,392,786; 6,413,790; 6,422,687; 6,445,374; 6,445,489; 6,459,418; 6,473,072; 6,480,182; 6,498,114; 6,504,524; 6,506,438; 6,512,354; 6,515,649; 6,518,949; 6,521,489; 6,531,997; 6,535,197; 6,538,801; 6,545,291; 6,580,545; 6,639,578; 6,652,075; 6,657,772; 6,664,944; 6,680,725; 6,683,333; 6,704,133; 6,710,540; 6,721,083; 6,724,519; 6,727,881; 6,738,050; 6,750,473; 6,753,999; 6,816,147; 6,819,471; 6,822,782; 6,825,068; 6,825,829; 6,825,970; 6,831,769; 6,839,158; 6,842,167; 6,842,279; 6,842,657; 6,864,875; 6,865,010; 6,866,760; and 6,870,661; and U.S. Patent Applications Publication Nos. 2002/0060321; 2002/0063661; 2002/0090980; 2002/0113770; 2002/0130832; 2002/0180687; 2003/0011560; 2003/0020844; 2003/0025855; 2003/0102858; 2003/0132908; 2003/0137521; 2003/0151702; 2003/0214695; 2003/0222315; 2004/0012839; 2004/0014265; 2004/0027327; 2004/0075634; 2004/0094422; 2004/0105036; 2004/0112750; 2004/0119681; 2004/0136048; 2004/0155857; 2004/0180476; 2004/0190114; 2004/0196215; 2004/0226820; 2004/0233509; 2004/0239614; 2004/0252360; 2004/0257635; 2004/0263947; 2005/0000813; 2005/0001812; 2005/0007336; 2005/0007653; 2005/0012980; 2005/0017944; 2005/0018273; 2005/0024353; 2005/0035941; 2005/0041004; 2005/0062714; 2005/0067656; and 2005/0078099; and International Applications Publication Nos. WO 99/67678; WO 00/05704; WO 00/38000; WO 00/36560; WO 00/67110; WO 00/67327; WO 01/07961; and WO 03/107,315.
Known electrophoretic media, both encapsulated and unencapsulated, can be divided into two main types, referred to hereinafter for convenience as "single particle" and "dual particle" respectively. A single particle medium has only a single type of electrophoretic particle suspended in a suspending medium, at least one optical characteristic of which differs from that of the particles. (In referring to a single type of particle, we do not imply that all particles of the type are absolutely identical. For example, provided that all particles of the type possess substantially the same optical characteristic and a charge of the same polarity, considerable variation in parameters such as particle size and electrophoretic mobility can be tolerated without affecting the utility of the medium.) When such a medium is placed between a pair of electrodes, at least one of which is transparent, depending upon the relative potentials of the two electrodes, the medium can display the optical characteristic of the particles (when the particles are adjacent the electrode closer to the observer, hereinafter called the "front" electrode) or the optical characteristic of the suspending medium (when the particles are adjacent the electrode remote from the observer, hereinafter called the "rear" electrode, so that the particles are hidden by the suspending medium).
A dual particle medium has two different types of particles differing in at least one optical characteristic and a suspending fluid which may be uncolored or colored, but which is typically uncolored. The two types of particles differ in electrophoretic mobility; this difference in mobility may be in polarity (this type may hereinafter be referred to as an "opposite charge dual particle" medium) and/or magnitude. When such a dual particle medium is placed between the aforementioned pair of electrodes, depending upon the relative potentials of the two electrodes, the medium can display the optical characteristic of either set of particles, although the exact manner in which this is achieved differs depending upon whether the difference in mobility is in polarity or only in magnitude. For ease of illustration, consider an electrophoretic medium in which one type of particles is black and the other type white. If the two types of particles differ in polarity (if, for example, the black particles are positively charged and the white particles negatively charged), the particles will be attracted to the two different electrodes, so that if, for example, the front electrode is negative relative to the rear electrode, the black particles will be attracted to the front electrode and the white particles to the rear electrode, so that the medium will appear black to the observer. Conversely, if the front electrode is positive relative to the rear electrode, the white particles will be attracted to the front electrode and the black particles to the rear electrode, so that the medium will appear white to the observer.
It should be noted that opposite charge "dual particle" media may contain more than two types of particle. For example, the aforementioned U.S. Pat. No. 6,232,950 illustrates, in FIGS. 6–9C, an opposite charge encapsulated triple particle system having three differently colored types of particles in the same capsule; this patent also describes driving methods which enable the capsule to display the colors of the three types of particles. Even more types of particles may be present; it has been found empirically that up to five different types of particles can usefully be present in such displays.
If the two types of particles have charges of the same polarity, but differ in electrophoretic mobility (this type of medium may hereinafter to referred to as a "same polarity dual particle" medium), both types of particles will be attracted to the same electrode, but one type will reach the electrode before the other, so that the type facing the observer differs depending upon the electrode to which the particles are attracted. For example suppose the previous illustration is modified so that both the black and white particles are positively charged, but the black particles have the higher electrophoretic mobility. If now the front electrode is negative relative to the rear electrode, both the black and white particles will be attracted to the front electrode, but the black particles, because of their higher mobility will reach it first, so that a layer of black particles will coat the front electrode and the medium will appear black to the observer. Conversely, if the front electrode is positive relative to the rear electrode, both the black and white particles will be attracted to the rear electrode, but the black particles, because of their higher mobility will reach it first, so that a layer of black particles will coat the rear electrode, leaving a layer of white particles remote from the rear electrode and facing the observer, so that the medium will appear white to the observer: note that this type of dual particle medium requires that the suspending fluid be sufficiently transparent to allow the layer of white particles remote from the rear electrode to be readily visible to the observer. Typically, the suspending fluid in such a display is not colored at all, but some color may be incorporated for the purpose of correcting any undesirable tint in the white particles seen therethrough.
Both single and dual particle electrophoretic displays may be capable of intermediate gray states having optical characteristics intermediate the two extreme optical states already described.
Some of the aforementioned patents and published applications disclose encapsulated electrophoretic media having three or more different types of particles within each capsule. For purposes of the present application, such multi-particle media are regarded as sub-species of dual particle media.
Also, many of the aforementioned patents and applications recognize that the walls surrounding the discrete microcapsules in an encapsulated electrophoretic medium could be replaced by a continuous phase, thus producing a so-called "polymer-dispersed electrophoretic display", in which the electrophoretic medium comprises a plurality of discrete droplets of an electrophoretic fluid and a continuous phase of a polymeric material, and that the discrete droplets of electrophoretic fluid within such a polymer-dispersed electrophoretic display may be regarded as capsules or microcapsules even though no discrete capsule membrane is associated with each individual droplet; see for example, the aforementioned U.S. Pat. No. 6,866,760. Accordingly, for purposes of the present application, such polymer-dispersed electrophoretic media are regarded as sub-species of encapsulated electrophoretic media.
A related type of electrophoretic display is a so-called "microcell electrophoretic display". In a microcell electrophoretic display, the charged particles and the suspending fluid are not encapsulated within microcapsules but instead are retained within a plurality of cavities formed within a carrier medium, typically a polymeric film. See, for example, International Application Publication No. WO 02/01 281, and published US Application No. 2002/0075556, both assigned to Sipix Imaging, Inc.
Although electrophoretic media are often opaque (since, for example, in many electrophoretic media, the particles substantially block transmission of visible light through the display) and operate in a reflective mode, many electrophoretic displays can be made to operate in a so-called "shutter mode" in which one display state is substantially opaque and one is light-transmissive. See, for example, the aforementioned U.S. Pat. Nos. 6,130,774 and 6,172,798, and 5,872,552; 6,144,361; 6,271,823; 6,225,971; and 6,184,856. Dielectrophoretic displays, which are similar to electrophoretic displays but rely upon variations in electric field strength, can operate in a similar mode; see U.S. Pat. No. 4,418,346.
Shutter mode displays can be used as conventional reflective displays, for example, by using particles having one color and providing a surface of a different color positioned on the opposed side of the electro-optic medium from the viewing surface through which an observer views the display; see, for example, the International U.S. Patent No. 6,177,921. Alternatively, shutter mode displays can be used as light modulators, that is to say devices which in one (open or transparent) optical state allows light to pass therethrough, while in another (closed or opaque) optical state the light is blocked.
One potentially important market for electrophoretic media is windows with variable light transmission. As the energy performance of buildings and vehicles becomes increasingly important, light modulators could be used as coatings on windows to enable the proportion of incident radiation transmitted through the windows to be electronically controlled by varying the optical state of the modulator. Such electronic control can supersede "mechanical" control of incident radiation by, for example, the use of window blinds. Effective implementation of such "variable-transmissivity" ("VT") technology in buildings is expected to provide (1) reduction of unwanted heating effects during hot weather, thus reducing the amount of energy needed for cooling, the size of air conditioning plants, and peak electricity demand; (2) increased use of natural daylight, thus reducing energy used for lighting and peak electricity demand; and (3) increased occupant comfort by increasing both thermal and visual comfort. Even greater benefits would be expected to accrue in an automobile, where the ratio of glazed surface to enclosed volume is significantly larger than in a typical building. Specifically, effective implementation of VT technology in automobiles is expected to provide not only the aforementioned benefits but also (1) increased motoring safety, (2) reduced glare, (3) enhanced mirror performance (by using an electro-optic coating on the mirror), and (4) increased ability to use heads-up displays. Other potential applications of VT technology include privacy glass and glare-guards in electronic devices.
Hitherto, relatively little consideration appears to have been given to the exact manner in which the electrophoretic particles move when electrophoretic shutter mode displays, including light modulators, move between their open and closed optical states. As discussed in the aforementioned copending application Ser. No. 10/907,140, the open state is brought about by field dependent aggregation of the electrophoretic particles; such field dependent aggregation may take the form of dielectrophoretic movement of electrophoretic particles to the lateral walls of a capsule or microcell, or "chaining", i.e., formation of strands of electrophoretic particles within the capsule or microcell, or possibly in other ways. Regardless of the exact type of aggregation achieved, such field dependent aggregation of the electrophoretic particles causes the particles to occupy only a small proportion of the viewable area of each capsule or microcell, as seen looking perpendicular to the viewing surface through which an observer views the medium. Thus, in the transparent state, the major part of the viewable area of each capsule or microcell is free from electrophoretic particles and light can pass freely therethrough. In contrast, in the opaque state, the electrophoretic particles are distributed throughout the whole viewable area of each capsule or microcell (the particles may be uniformly distributed throughout the volume of the suspending fluid or concentrated in a layer adjacent one major surface of the electrophoretic layer), so that no light can pass therethrough.
European Patent Application No. 709,713 describes several different types of shutter mode electrophoretic displays which rely upon chaining of the electrophoretic particles. These shutter mode electrophoretic displays are of two principal types. In the first type, as shown for example in FIGS. 1–6 of this Application, chaining occurs between two unpatterned electrodes on either side of an electrophoretic medium, which comprises electrophoretic particles in an insulating fluid, typically a silicone oil. The electrophoretic particles themselves comprise a polymeric core with an outer inorganic layer formed from an electrically semiconductive material, an inorganic ion exchanger, silica gel or one of these materials doped with a metal. Such electrophoretic particles are likely to be difficult and expensive to manufacture, but are apparently required because the chaining of the particles requires polarizable particles; conductive particles cannot be used since they would short the electrodes when chaining occurs. The operating voltage appears to rather high; the recommended field across the electrophoretic medium is 0.25 kV/mm to 1.5 kV/mm, or 25 to 150 volts for a 100 μm thick electrophoretic layer. The closing of the display (i.e., the transition from its light transmissive to its opaque state) is effected by diffusion of the particles throughout the electrophoretic medium, and hence will be slow. Furthermore, such a display is stable only in its closed state.
In the second type of shutter mode display described in European Patent Application No. 709,713 (see FIGS. 31 and 32B thereof), one electrode is unpatterned, but the opposing electrode is formed as a series of narrow parallel strips, divided into two alternating sets with provision for applying different voltages to the two sets. In the open optical state of such a display, all the strips are set to the same voltage, which is different from that of the unpatterned electrode, so that chains are formed between the unpatterned electrode and each of the strips. In the closed optical state of the display, differing voltages are applied to the two sets of strips, so that chaining occurs between adjacent strips; the voltage applied to the unpatterned electrode is essentially irrelevant, provided it is intermediate the voltages applied to the two sets of strips. This type of display uses the same complex electrophoretic particles as the first type of display described above. In addition, it appears doubtful that the closed state of such a display would be completely dark, since there will inevitably tend to be some gaps between adjacent chains in the closed state and even a small proportion of such gaps will adversely affect the darkness of the closed state. Although this second type of display will close more quickly than the first type described above, since it can be actively driven to its closed state rather than relying upon diffusion, it is not truly bistable in either optical state. Finally, especially in high resolution displays, the formation of the necessary narrow strip electrodes presents manufacturing problems.
The present invention relates to shutter mode electrophoretic displays, including light modulators, which do not suffer from the disadvantages of the prior art displays discussed above.


Disclosed are techniques for accurately determining network latency. The techniques include steps for transmitting a latency packet between a network test device and a remote network node. The techniques particularly include steps for recording timestamps upon transmission and receipt of the latency packet by the respective network device and the remote network node. Network latency is determined based on a difference between timestamps of the network device (transmitting and receiving the latency packet) and a difference between the timestamps of the remote network node (transmitting and receiving the latency packet).

1. Field of the Invention The present disclosure relates to network testing, and more particularly, to determining latency of a communication network with limited computing resources.
2. Description of the Related Art
Network latency or network delay affects overall performance of communication networks. Network latency indicates how long it takes for data to travel from one node to another node in a communication network, which latency typically differs depending on various network conditions (e.g., locations of specific pairs of communicating nodes, types of protocols, communication medium, etc.).
Determining network latency amongst various network nodes is important for numerous network testing and design scenarios. With respect to network testing, measuring latency, in some scenarios, typically includes transmitting a data packet (e.g., an Internet Protocol (IP) packet) from a source node to a remote node (e.g., via Internet Control Message Protocol (ICMP) Echo Requests (e.g., Ping, etc.)) and receiving a reflected IP packet from the remote node. Latency is determined by the time it takes for the data packet to be transmitted from the source node, reflected by the remote node, and ultimately received back at the source node. However, when the data packet is reflected from the remote node, the data packet is typically subjected to additional processing (e.g., propagation through the remote node's network stack such as the four
Open Systems Interconnection (OSI) layers of respective remote nodes) prior to transmission or reflection of the data packet back to the source node. Additionally, the data packet may be subjected to similar additional processing by the source node upon receipt. All the additional processing can skew latency determinations due to varying hardware and/or software configurations of the source node and remote node resulting in inaccurate latency determinations.
Despite efforts to date, there is still a need in the art for improved systems, methods and apparatus to accurately determine latency in communication networks. The present invention provides a solution for these problems.

Determining network latency with limited computing resources


A method for providing driving assistance based on a HD map includes acquiring information such as position of a vehicle and timing, and acquiring a speed of the vehicle based on the manner of driving, and acquiring distance an intersection in front of the vehicle and information from a HD map such as traffic light intersection ahead. Deciding such as whether the vehicle can pass through the intersection based on the speed of the vehicle, intersection distance, and the traffic light information and prompting and/or controlling the vehicle if it is determined that passage through is not possible. A vehicle-mounted apparatus applying the method is also disclosed.

Cars are ever more widespread and traffic safety becomes more important. While negotiating traffic lights, drivers always estimate whether there is an enough time for passing through by driving experience. An incorrect evaluation may be catastrophic. Communications between vehicles and communications between vehicles and traffic light terminals are commonplace. Images of the traffic light of an intersection in front of a vehicle can be captured by a camera in the vehicle. There is no prompt information based on the captured images of traffic light and the location of the current vehicle.
Thus, there is room for improvement in the art.

Method for providing assistance to driver based on HD map, and vehicle apparatus applying method


A molecular marker expressed specifically in corneal endothelial cells, and a method for producing one or more corneal endothelial cells using the marker and a method for evaluating one or more corneal endothelial cells using the marker are provided. At least one molecule selected from the group consisting of ZP4, MRGPRX3, GRIP1, GLP1R, HTR1D, and CLRN1 is used as a marker specific to corneal endothelial cells.

The cornea is the transparent front part of the eyeball. From the anterior, the cornea has a corneal epithelium, a Bowman's membrane, a corneal stroma, a Descemet's membrane, and a corneal endothelium. The corneal epithelium is present at the outermost part of the cornea, and functions as a barrier to protect the cornea from foreign matter, such as dust and bacteria. The Bowman's membrane is thought to function as a base for the corneal epithelium. The corneal stroma is the thickest layer among the three layers (i.e., corneal epithelium, corneal stroma, and corneal endothelium), and maintains the strength of the cornea. The Descemet's membrane is located beneath the corneal stroma, and connects the corneal stroma with the corneal endothelium. The corneal endothelium is a monolayer in which hexagonal corneal endothelial cells are regularly arranged like cobblestones; it plays a critical role in maintaining the transparency of the cornea by preventing, by its barrier and pumping functions, the moisture in the anterior chamber from penetrating into the corneal stroma, while maintaining the fluid balance by draining the moisture in the cornea out to the anterior chamber.
Loss of a significant number of corneal endothelial cells due to cell damage caused by genetic or external factors impairs the functions described above, leading to corneal edema. Severe corneal endothelial dysfunction compromises the maintenance of the transparency of the cornea. If bullous keratopathy develops, marked visual loss may result.
Corneal endothelial cells have a very limited capacity for proliferation in the human body. The most effective, fundamental method to treat severe corneal endothelial dysfunction at the moment is corneal transplantation. In fact, bullous keratopathy is the disease for which corneal transplantation has been most often performed. Although full-thickness cornea transplants have, in the past, been performed for corneal endothelial dysfunction, there are problems such as a chronic donor shortage and transplant rejection. To minimize rejection, a technique has been developed that transplants only a partial tissue containing a corneal endothelium to an eye with a disorder (Descemet's Stripping Automated Endothelial Keratoplasty: DSAEK). However, DSAEK also cannot overcome the donor shortage. Attempts to grow corneal endothelial cells in vitro and use the cells in treatment have also been made (Non-patent Literature 1 and Patent Literature 1 to 3). However, repeated passages cause genetic transformation, leading to loss of their functions (Non-patent Literature 2).
To solve the problems described above, a number of studies have been conducted on induction of corneal endothelial cells from umbilical cord blood-derived mesenchymal stem cells (Non-patent Literature 3), bone marrow-derived cells (Non-patent Literature 4), iris-derived stem cells (Non-patent Literature 5), corneal stroma-derived stem cells (Non-patent Literature 6), embryonic stem cells (Non-patent Literature 7), induced pluripotent stem cells (Patent Literature 4), etc., for the purpose of transplant. However, regardless of the origin of the cells, the thus-obtained cultured cells contain different types of cells in addition to corneal endothelial cells. In these studies, therefore, a marker specific to corneal endothelial cells usable to isolate and evaluate corneal endothelial cells (i.e., its target product) is indispensable.
Currently, proteins, such as ZO-1 (Non-patent Literature 8), Na+—K+-ATPase (Non-patent Literature 9), and N-cadherin (Non-patent Literature 10), are used as corneal endothelial cell markers. These proteins, however, are expressed non-specifically in many other types of cells (Non-patent Literature 11 to 13). Thus, isolation of corneal endothelial cells using these proteins is not expected to give a satisfactory outcome, in particular given the multilineage potential of the stem cells used to induce differentiation into corneal endothelial cells.


A screen covering (1) comprising:                several cross-beams (2) arranged so as to be slidable away from each other and towards each other;        a screen (3) supported by the cross-beams (2) and foldable between the cross-beams (2) at sliding of the cross-beams (2);        and a lateral gutter (4), which extends essentially perpendicular to the cross-beams (2) and is arranged below a lateral side of the screen (3);wherein said lateral side of the screen (3) is provided with a downwardly extending drip guard (5), which is foldable at sliding of the cross-beams (2).

Screen coverings of this type are usually erected in order to cover or to clear an outdoor area. By sliding the cross-beams away from each other, the screen can be extended to cover the area below the screen and by sliding the cross-beams towards each other, the screen is folded, such that this area can be cleared.
Such screen coverings are thus often erected at residences, restaurants, shops and the like in order to shield an outdoor terrace or the like from the sun, precipitation and/or wind or conversely to allow sunshine in temporarily. Said screen coverings may be configured in the form of awnings, pergolas, verandas, terrace coverings, carports, etc.
With such type of screen coverings it is difficult to arrange a said lateral gutter below the lateral side of the screen, allowing draining of precipitation along this lateral side of the screen and yet allowing the screen to fold above this lateral gutter. In order for precipitation to drain off into the gutter, an inner side wall of the lateral gutter is arranged underneath the screen and an outer side wall of the lateral gutter extends beside the screen. In order to enable the screen to fold, the screen however needs to be arranged at a certain distance with respect to the inner side wall of the lateral gutter. The inner side wall cannot be made sufficiently high to ensure that precipitation is kept inside the lateral gutter. With lateral drainage of precipitation, a known problem is therefore dripping of precipitation along the lateral sides of the screen, falling next to the inner side wall of the lateral gutter, in the area below the screen.
In order to solve this problem, several solutions have been proposed yet.
The lateral gutter or parts thereof have already been arranged moveable, in order to bring the inner side wall closer to the position where the precipitation falls from the screen, in order to minimize dripping and in order to assure at folding of the screen, that this inner side wall does not hinder the screen to fold above this lateral gutter.
In EP 1 842 980 A1 the lateral sides of the screen are provided with edge portions, preventing precipitation from overflowing, and the cross-beams are provided with cross channels for discharging precipitation through draining end portions of the cross-beams.
In EP 2 578 767 A2 an upwardly protruding band is arranged over the whole lateral side of the screen, preventing precipitation from draining along this lateral side and guiding precipitation towards the front for draining into a front gutter. Draining at the front however requires a steeper inclination of the screen, which is often undesired.
In WO 2013/169217 precipitation is prevented from dripping along the lateral sides of the screen, by means of a seal which is arranged above the screen.


A method and system for managing handoff of a cellular wireless data session between a first wireless coverage area and second wireless coverage area. A first radio network controller (RNC) predicts that handoff of the data session will soon be necessary. Radio resources for continuing the data session in the second wireless coverage area are reserved. The reserved radio resources may be controlled by the first RNC or by a second RNC. The first RNC sends, to a wireless communication device, a predictive handoff directive message that instructs the wireless communication device (i) to wait a designated period of time, and (ii) to then handoff the data session.

1. Field of Invention
The present invention relates to wireless communication devices that participate in wireless data sessions, and more particularly to hand off wireless data sessions from a first entity to a second entity.
2. Description of Related Art
In a cellular wireless data communication system, an area is divided into a plurality of cells, each defined by a radiation pattern from a respective base transceiver station (BTS). Each BTS is in turn coupled with a radio network controller (RNC), and each RNC is then coupled with a gateway such as a packet data serving node (PDSN), which provides connectivity with a packet-switched network such as the Internet. In a typical arrangement, each RNC serves a plurality of BTSs, and each PDSN serves a plurality of RNCs. Further, each cell is typically divided into a plurality of sectors. A wireless communication device may then operate within the coverage area of a given sector and communicate, wirelessly with the BTS and via the RNC and PDSN, with an apparatus on the packet-switched network.
Generally speaking, the RNC functions to manage allocation of radio resources, such as to allocate radio traffic channels for use by wireless communication devices and to manage handoff of wireless communication device communications between coverage areas served by the RNC. Further, the RNC functions as an interface between wireless communication devices and the PDSN, so as to facilitate establishment of packet-data connectivity for wireless communication devices.
Air interface communications between the BTS/RNC and wireless communication devices can comply with various protocols, examples of which include CDMA, TDMA, GSM, and AMPS. This description will focus on CDMA, although it should be understood that the principles described herein can be extended to apply with respect to other air interface protocols as well.
In CDMA, each sector is identified by a unique "PN offset" in a given carrier frequency, and a wireless communication device communicates with its serving BTS on one or more coded traffic channels each identified by a unique "Walsh code." High speed data communications under the emerging 1XEV-DO standard (IS-856) occur within a common traffic channel (i.e., using a common Walsh code), with each wireless communication device being assigned to communicate on a particular TDM time slot in the channel.
To acquire packet-data connectivity, according to IS-856, a wireless communication device first sends to its RNC a packet-data-connectivity request called a UATI (Universal Access Terminal Identifier) request. This is an IP-based message, which passes over an all IP channel between the wireless communication device and the RNC. (For this purpose, the wireless communication device has a local non-routable IP address usable for communications with the RNC.)
Once the RNC receives the UATI request from the wireless communication device, the RNC authenticates the wireless communication device and facilitates assignment of a mobile-IP address for use by the wireless communication device. In particular, the RNC sends an access request to an Access Network AAA (ANAAA) over an A12/13 interface, and the ANAAA authenticates the wireless communication device. The RNC then assigns radio resources for the data session, by directing the wireless communication device to operate on a particular TDM time slot in the common data traffic channel on a given carrier frequency. Further, the RNC signals to the PDSN, and the PDSN and wireless communication device then negotiate to establish a point-to-point protocol (PPP) data link connection. In addition, the PDSN signals to a mobile-IP home agent (HA), which assigns a mobile-IP address for the wireless communication device to use, and the PDSN passes that IP address via the RNC to the wireless communication device. Given its radio link (TDM time slot/frequency), data link (PPP link with the PDSN) and IP address, the wireless communication device may then begin communicating with an apparatus on the packet-switched network.
As noted above, one of the functions of the RNC is to manage handoffs of wireless communication device communications between coverage areas. In typical practice, handoff is triggered based on an analysis of the strength of pilot signals that a wireless communication device is receiving from its current serving sector and from adjacent sectors. If the strength of the pilot signal from an adjacent sector exceeds the strength of the pilot signal from the current sector by a threshold level, then handoff will occur. In CDMA, a wireless communication device has an "active set" of sectors in which it operates concurrently. Consequently, handoff may occur when the strength of a pilot signal from an adjacent sector (not in the active set) exceeds the lowest strength of a pilot signal in the active set by a defined threshold level, TADD.
Handoff can be mobile-initiated or network-initiated. In a mobile-initiated handoff system, the wireless communication device regularly analyzes its received signal strength to determine when the strength of a pilot signal from an adjacent sector exceeds the strength of the pilot signal from the current sector by the threshold and, if so, notifies the RNC. The RNC may then responsively direct the wireless communication device to hand off to the new sector. In a network-initiated handoff system, on the other hand, the wireless communication device regularly sends measurements of its received signal strength to the RNC, and the RNC determines when the received signal strength of a pilot signal from an adjacent sector exceeds the received signal strength from a current sector by the threshold and, if so, directs the wireless communication device to hand off to the new sector.
This handoff process is largely seamless when the source and target sectors for the handoff are both within the same RNC serving area. However, difficulty arises when the source and target sectors are served by different RNCs. When that happens, the handoff process contemplated by IS-856 involves releasing the wireless communication device's radio link (TDM time slot) with respect to the first RNC and then forcing the wireless communication device to re-acquire a radio link with respect to the second RNC.
More particularly, when the first RNC detects that the wireless communication device should hand off to a sector served by the second RNC, the first RNC will transition the wireless communication device into a "dormant" state in which the wireless communication device will maintain its data link (PPP session) and IP address but in which it will have no radio link. To do so, (i) the first RNC will signal over a forward link control channel to the wireless communication device, to tell the wireless communication device that the wireless communication device's assigned TDM time slot is being released and that the wireless communication device should operate on the target sector's PN offset instead, (ii) the first RNC will release the assigned TDM time slot, and (iii) the first RNC will signal to the PDSN to direct the PDSN to put the wireless communication device into a dormant state, thereby causing the PDSN to begin buffering any packets that arrive for the wireless communication device.
When the wireless communication device receives the message indicating that it has lost its traffic channel, the wireless communication device will automatically seek to re-acquire packet-data connectivity by sending a UATI message in the target sector. As the target sector is served by the second RNC, the UATI message will then pass to the second RNC. In response, the second RNC will then assign a TDM time slot for use by the wireless communication device.
Further, after the second RNC assigns the TDM time slot, the second RNC can send a signal to the PDSN in response to the UATI message. In order for the second RNC to be able to signal the PDSN, the second RNC needs to know the IP address of the PDSN. The second RNC may learn the IP address of the PDSN in various ways. As an example, the wireless communication device may send the IP address of the PDSN to the second RNC via the assigned TDM time slot for the target sector. As another example, the first RNC may send a message that indicates the IP address of the PDSN to the second RNC prior to handoff of the data session. Other examples of how the second RNC learns the IP address of the PDSN are also possible. After learning the IP address of the PDSN, the second RNC, in response to the UATI message, can signal the PDSN to transition the wireless communication device back to an "active" state.
The transitioning of the wireless communication device's data session from active to dormant and then back to active again, to facilitate a handoff from a first RNC to a second RNC, can disrupt data communications and is generally inefficient. Therefore, an improvement is desired.

Method and system for predictive handoff of a data session between entities


Pressureless sintered high density materials containing hexagonal boron nitride have low coefficients of friction and high wear resistance and are useful for bearings, bushings and other articles subjected to bearing loads.

1. Field of Invention
The present invention relates to a method for producing high density materials with intrinsic, unabradable slipperiness and, more particularly, materials having low coefficients of friction and wear rates and containing hexagonal boron nitride.
2. Description of Prior Art
Friction, defined in the context of this invention as the resistance to movement of one solid body over another, is essential to the proper course of many physical, biological and industrial processes. In a vast number of situations however, it is disadvantageous, resulting in loss of power, generation of heat and wear of the surfaces in contact. Consequently, wherever friction constitutes a problem, the prior art has endeavored to lower the coefficient of friction of the surfaces in relative motion to one another.
In one approach, a film of fluid lubricant is interposed between the moving surfaces. While traditional fluid lubricants such as vegetable and mineral oils, greases and animal fats still hold their place in many modern industrial applications, they do not possess the properties necessary to effectively function as engine lubricants, transmission fluids, gear oils, hydraulic and metalworking fluids and other high performance lubricants. Also, new high performance lubricant formulations are constantly required to overcome the shortcomings of existing products and to meet the demands of advancing technology. A significant example is the development of inorganic solid lubricants for applications involving severe temperatures, pressures and environments which would preclude the use of organic fluids.
Solid lubrication is based on ductile shear within a solid lubricant film caught between moving surfaces. Consequently, solid lubricants must have low shear strength, a property they share with fluid lubricants. The most widely used solid lubricants, graphite and molybdenum disulfide, as well as a number of other dichalcogenides provide this property through slip along preferred crystallographic planes. Solid lubricants should also have low abrasivity, i.e. they should be softer than the surfaces they lubricate to avoid causing abrasive wear to the latter. Finally, they should be thermodynamically and chemically stable in the environment in which they are to function. Yet, all of the solid lubricants mentioned so far suffer thermal decomposition or oxidative degradation at temperatures above 500-600° C. In addition, graphite is electrically conductive and reactive with ferrous alloys. To transcend these limitations, the prior art has turned to hexagonal boron nitride (h-BN).
Hexagonal boron nitride (h-BN) powder is synthesized by nitridation or ammonolysis of boron trioxide at temperatures ranging from 800° C. to 2000° C. During h-BN powder synthesis, edge-fused six-atom (B—N)3 hexagonal rings crystallize into two-dimensionally-stacked layers of h-BN macromolecules. Different crystalline structures can be obtained by changing process conditions. During the initial stage of crystallization, from 800° C. to about 1200° C., h-BN macromolecules grow into hexagonal primary crystallites of approximately 10 nm width termed turbostratic boron nitride (t-BN). During the next step of the crystallization process, from about 1200° C. to about 1800° C., the crystallites coalesce, roughly tripling their size to about 30 nm into so-called mesographitic boron nitride (m-BN). During the final stage of crystallization, from about 1800° C. to 2000° C. the crystallites again roughly triple their size to about 90 nm, arranging themselves into regularly stacked layers with the B atoms in the rings in one layer above and below N atoms in the rings of contiguous layers in what is called graphitic or fully crystallized hexagonal boron nitride (h-BN). It will be noted that the term hexagonal boron nitride (h-BN) is ambiguous as it is used to designate both the generic hexagonal crystalline structure of boron nitride—as distinct from other crystalline structures such as cubic boron nitride (c-BN)—as well as the fully crystallized graphitic boron nitride.
In the stacked layer arrangement of hexagonal boron nitride (h-BN), the polar interplanar B—N bond between adjacent layers is longer and therefore weaker than the strong covalent intraplanar B—N bonds in the fused six-atom rings. As a result, h-BN crystal grains are easily cleft into flakes liable to slip relative to one another, hence exhibiting solid lubricity. Hexagonal boron nitride (h-BN) is useful as both a low temperature and high-temperature solid lubricant or in applications where the electrical conductivity or chemical reactivity of graphite would constitute a problem. Like other solid lubricants, h-BN films are commonly applied by burnishing, thermal spraying, electrodeposition, chemical or physical vapor deposition.
Hexagonal boron nitride powders have also found use in fluid film lubrication. Denton et al., U.S. Pat. No. 5,589,443 teaches an h-BN-filled grease composition for lubricating journal bearings in rock bits used for oil well drilling. Watari et al., U.S. Pat. No. 5,985,802 discloses a high-performance cutting or grinding oil containing a dispersion of fine h-BN powders.
In another use of h-BN toward reducing the coefficient of friction, the prior art has resorted to various coatings and treatments of the surfaces in relative motion to one another. In one such instance, Brown, U.S. Pat. No. 6,576,698 teaches surface coatings for firearm projectiles and firearm components such as gun barrels composed of thermosetting resins filled with fine h-BN particles.
In cases where neither solid lubricant films nor surface treatments are indicated to lower the coefficient of friction of surfaces in relative motion to one another, the prior art has endeavored to replace the system components displaying excessive friction with components made from materials having an intrinsic lower coefficient of friction. For example, in replacement of the lead-containing aluminum and copper alloys used by the prior art for journal bearings and bushings and other articles subject to high bearing loads, Dunmead et al., U.S. Pat. No. 6,837,915, (Dunmead) teaches hot isostatically processed, lead-free, high theoretical density, h-BN-containing metal alloys having low coefficients of friction and wear rates. Dunmead claims that the amount of h-BN needed to result in a reduction of at least 20% of the coefficient of friction concomitant with a reduction of not more than 10% of the yield strength of the boron nitride-free matrix material is 2-5 weight percent. Metals amenable to Dunmead's invention include iron, carbon steel, stainless steel, chromium, aluminum, copper, brass, bronze and other copper based alloys. While Dunmead's invention constitutes a major improvement over the prior art in providing high density, wear-resistant materials with low coefficients of friction—thereby obviating the recourse to circuitous techniques such as fluid lubrication or surface treatments—materials amenable to his invention are limited to hot isostatically processable metallic alloys. Also, hot isostatic pressing, being a cost-intensive process, is generally uneconomical for mass production and frequently necessitates secondary machining if the shapes of the end products are somewhat complex.
Consequently, the prior art has turned to pressureless sintering. However, attempts at pressureless sintering of either pure h-BN or h-BN dispersed in a matrix have been largely unsuccessful due to boron nitride's reluctance to sinter as a result of the strong covalent bonds on the crystal basal planes.
For instance, Hagio et al., in the above cited reference, describes pressureless sintering of cold-pressed compacts of pure h-BN powders at 2000° C. for 1 hour without achieving any densification at all.
Likewise, Pickens et al., in the above cited reference, reports on pressureless sintering of cold-pressed structures composed of alternating layers of silicon nitride and boron nitride at 1800° C. for 3 hours resulting in poor densification with ensuing inferior mechanical properties.
Ciloglu et al., U.S. Pat. No. 4,927,461 (Ciloglu) discloses pressureless sintering of ferrous powder metallurgy (P/M) compacts containing h-BN powder. However, Ciloglu only aims at improving machinability and, therefore, the amount of h-BN powder added to the ferrous matrix is infinitesimal, from 0.01 to 0.5 weight percent, i.e. far below Dunmead's aforementioned optimum 2-5 weight percent necessary to reduce the coefficient of friction by at least 20%. Significantly, Ciloglu's matrix is a typical ferrous P/M powder with a maximum particle size of 300 μm.
Braillard et al., U.S. Pat. No. 7,128,962 (Braillard) claims pressureless partial sintering of materials containing 10-40 volume percent of boron nitride agglomerates having an equivalent diameter of 5-200 μm with, the explicit intention of rendering the resulting matrix composite abradable. Braillard emphatically excludes any alloys containing nickel on the grounds of severe incompatibility between nickel and boron. This inherently eliminates a large number of stainless steels and superalloys from the reach of his invention. Significantly, Braillard's metal matrix alloy powder has a particle size range of 10-70 μm.
Cherubini et al., (Cherubini) in the above cited reference, reports on attempts to pressureless sinter cold-pressed compacts of minus 100 mesh (149 μm) type 304 stainless steel powder blended with minus 325 mesh (44 μm) boron nitride powder resulting in precipitation of a boron-rich phase throughout the stainless steel matrix.
Chou, T. C., (Chou) in the above cited reference, reports interfacial reactions during the chemical interdiffusion between boron nitride and Ni3Al with concomitant formation of Kirkendall voids.
Benko, E., (Benko) reporting in the above cited reference on the study of BN-metal systems, determines that the metals react with boron nitride forming borides or mixtures of borides and nitrides.
In the course of the development toward the present invention, attempts at pressureless sintering of h-BN containing matrix composites under conditions of temperature, pressure and atmosphere commonly used to sinter the corresponding boron nitride-free matrix material invariably failed, resulting in segregation of boron-rich precipitates. For example, the usual sintering temperature for boron nitride-free 304L stainless steel is about 1350° C. but when attempting to sinter 304L matrix composites containing 5 weight percent of h-BN at that temperature, liquid phase exuded from the matrix.
From the foregoing description of the prior art, it can be gathered that the ability to extend the reach of Dunmead's invention to a wider range of materials, that would encompass pure metals, metal alloys, oxides, nitrides, carbides, including cemented carbides, and mixtures of these, as well as the ability to reach the high densities essential to ensure wear resistance by pressureless sintering would be desirable and innovative improvements. However, the fabrication by pressureless sintering of highly densified boron nitride containing materials having low coefficients of friction and wear rates is not known.

High density materials with intrinsic unabradable slipperiness and method of fabrication thereof