Embodiments described herein relate to a device operable to process input for a picture password for proof of knowledge. In some embodiments, the device includes a display, an input subsystem, processor(s), and memory containing instructions executable by the processor(s) such that the device is operative to display, on the display of the device, an image for the picture password proof of knowledge. The image is associated with an overlaid grid comprising a plurality of elements, and each element corresponds to a distinct area of the image. The device is further operative to, determine an offset to be used and, in response to receiving an input via the input subsystem at a first location of the display, highlight an element of the overlaid grid at a second location on the first image on the display. The second location is offset from the first location by the offset.

Authentication mechanisms use one or more authentication factors to control access to secured information. An authentication mechanism may require a knowledge factor (e.g., a username and a password), an ownership factor (e.g., a hardware security token), an inherence factor (e.g., a biometric identifier such as a fingerprint), or combinations thereof. Thus, for example, authentication of a user on a web portal can involve "what you know," "what you have," and "who you are." The first of these is commonly referred to as proof of knowledge.
Authentication based on proof of knowledge includes an enrollment phase to define user knowledge and a use phase to authenticate a user that proves that knowledge. A non-limiting example of proof of knowledge is a technology known as "picture password" (see, e.g., Wayne Jansen et al., "Picture Password: A Visual Login Technique for Mobile Devices," National Institute of Standards and Technology, NISTIR 7030, July 2003). Similar picture password functionality has been incorporated into WINDOWS® 8 for logging into the WINDOWS® 8 operating system. A picture password includes a combination of one or more input actions associated with a known image (e.g., without limitation, a still picture, a motion picture with or without sound, a photograph, or the like) that may be used to authenticate a user who is able to prove his knowledge by repeating the input actions in conjunction with the image. Another non-limiting example of a proof of knowledge that uses a "picture password" is disclosed by U.S. Pat. No. 8,813,183 entitled METHOD AND SYSTEM FOR PROCESSOR OR WEB LOGON, which is incorporated herein by reference in its entirety. U.S. Pat. No. 8,813,183 discloses the use of an image and knowledge about that image that a user can readily remember for authentication.
Picture passwords can replace or supplement conventional passwords as proofs of knowledge. For example and without limitation, picture passwords can be used for web logins to access web accounts (e.g., without limitation, a bank account, a brokerage account, electronic billing, or a payment system). Thus, a picture password can replace a textual password, Personal Identification Number (PIN), or pass phrase (i.e., conventional passwords). A username is typically associated with any proof of knowledge because it is possible to have a non-unique conventional password. Although a picture password may be more unique than other conventional passwords, a unique username may still be required by a Relying Party (RP) (e.g., the bank providing the bank account, the brokerage firm providing the brokerage account, or the proprietor of the electronic billing or payment system) to ensure security.
Authentication mechanisms may also distinguish between human and machine input. Systems such as Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) provide a type of challenge-response test used in computing to determine whether or not a user is a human, instead of, for example, a "robot" or other type of computer agent seeking to thwart an authentication mechanism. A CAPTCHA protects websites against robots by generating and grading tests that humans can pass but current computer programs cannot. For example, human input is authenticated by displaying distorted text that only a human user can perceive and input.
It is believed that text-based passwords or picture passwords do not provide protections similar to those provided by CAPTCHA. However, picture password technology has a number of advantages over text-based passwords, including more entropy for fewer actions. Entropy refers to a lack of predictability of input actions and provides a measure of the strength of proof of knowledge.
Picture passwords have greater entropy because their corresponding vocabulary is larger than textual passwords that rely on a combination of characters. Vocabulary refers to the range of inputs used for authentication. Much of the difference in vocabulary size over text-based passwords results from a wide range of possible unique input actions over a range of locations on a unique image.
To prove user knowledge without actually recording a password, it is desirable to store a picture password as a cryptographic hash of input actions associated with an image. This almost always involves discretizing a displayed image into a grid that has multiple sections by using, for example, various tessellation techniques (e.g., without limitation, rectangular grids, hexagonal grids, or Voronoi tessellations). Further, vocabulary size for picture passwords decreases as error tolerance increases due to placement of the grid and tolerance of inputs at adjacent grid locations (e.g., without limitation, a tolerance of 9 for rectangular grids or 7 for hexagonal grids).
The use of touch-sensitive surfaces as input devices for electronic devices has increased significantly in recent years. As such, touch-sensitive surfaces are widely used as input devices to authenticate users. Examples of touch-sensitive surfaces include touch pads and touch screen displays.
For portable and/or handheld electronic devices with relatively small display screens, existing picture password methods are cumbersome, inefficient, and inaccurate. For example, a portable handheld device with a small screen (e.g., smartphones and other pocket-sized devices) displays a relatively small image for a picture password but still requires a high degree of accuracy to authenticate a user.
Current picture password systems may be fashioned by selecting a number of element(s) associated with an image in response to a gesture such as a stroke(s) that form drag paths on an image, including stroke(s) that form drag paths that avoid previous stroke(s) on the image. This situation creates a significant cognitive burden on a user that may have difficulty seeing and inputting actions on small display devices with sufficient accuracy to authenticate the user.
Thus, there is a problem when going from a relatively larger picture display to a relatively smaller picture display such as, for example and without limitation, going from a laptop display screen to a relatively smaller smartphone touch-sensitive display, while trying to preserve the entropy advantage of picture passwords. An input object such as a user's finger or stylus can be cumbersome to touch, swipe, or move along a path with sufficient precision to correctly select grid locations required for a picture password. In addition, users would prefer to use the same picture password created, for example, with a mouse on a high resolution display on a relatively smaller touch-sensitive display of a smartphone.
With the wide range of available display sizes (e.g., without limitation, desktop, laptop, tablet, smartphone, or wearable display screens) and the various types of pointer (e.g., cursor) interactions (e.g., without limitation, caused by a mouse, a gesture on a touch-sensitive display, or a "hoverscreen" with which a user can hover a hand or finger a distance away from the display surface and cause an action, such as flipping through an e-book or surfing the web, without causing a finger smudge), there is a need for a user input mechanism that allows the same picture password activity to be detected across all possible display sizes and cursor interaction types in a way that is seamless to a user. Accordingly, a need exists for devices, systems, and methods that employ picture passwords on relatively small display screens.

Method and system of providing a picture password for relatively smaller displays


A window shade particularly for use with a motor vehicle window including a shade supported at one edge by a winding shaft and a pull strip located at the other edge of the shade for unwinding the shade from the winding shaft. For guiding the movement of the shade onto and off the winding shaft, a guide device comprised of two pairs of toggle links is provided. Each pair of toggle links is attached by a pivot connection at one end. The opposite end of one toggle link is pivotably attached to a fixed location. The opposite end of the other toggle link is pivotably attached to the pull strip. A strut extends between the pivot locations where the two pairs of toggle link arms are connected. Each toggle link arm is connected to the strut at a main pivot and at a second location and the strut is slotted to receive both connections from each link arm and to permit the toggle links connections to move through an arcuate pathway as the pull strip is moved. At least one of the toggle link arms may be braked, resisting winding and unwinding of the shade.

The present invention relates to a window shade, particularly for automotive vehicles, having a winding shaft with a spring device tensioned in the rolling up direction. One edge of the shade is fastened to the shaft while its other edge is fastened to a graspable pull strip.
A window shade of this type is shown in Federal Republic of Germany Utility Model 79 02 405. In that known window shade, telescopic swing struts are provided for the opening and closing of the shade.
U.S. Pat. No. 1,441,487 shows a window shade of the present type which is useful for cars. This known window shade has a winding shaft which has spring means pretensioned in the rolling up direction. One edge of the shade is fastened to the shaft. The other edge is fastened to a pull strip. Between the winding shaft and the pull strip there is a guide mechanism which acts in the plane of the pulled down shade. That mechanism includes two pairs of toggle-like link arms. The free arms of both pairs of link arms are fastened for swinging around one of their ends to stationary parts of the car and at their other ends to the pull strip. In this known shade, particularly when the force is introduced eccentrically, there is no assurance that the movement down and up of the shade will always take place at right angles to the winding shaft. The same comments apply to the window shade shown and described in U.S. Pat. No. 1,442,255.


A gear change control system of an automatic transmission, include: a shift member, including a shaft portion which is disposed in such a manner that a selection axis thereof is oriented in a selecting direction and including an arm portion; shift fork portions, operable to make gear shifts of gears; shift rail members, connected to the sift fork portions and arranged in such a manner that shift axes thereof are oriented in a shifting direction; and shift lug members, projecting from the shift rail members and including pillar-shaped portions. The arm portion swings about the selection axis to apply a pressure in the shifting direction from one side of the pillar-shaped portion so as to cause the shift fork portion to perform a shift making operation, and to apply a pressure in the shifting direction from the other side of the pillar-shaped portion so as to cause the shift fork portion to perform a shift withdrawing operation.

1. Field of the Invention
The present invention relates to a gear change control system of an automatic transmission which is provided on a drive train of a vehicle.
2. Description of the Related Art
There is a mechanical automatic transmission which does not use a torque converter as a transmission provided on a drive train of a vehicle.
This mechanical automatic transmission obviates the necessity of a torque converter by implementing the actuation of gear change control (selection and implementation of a gear shift) and engagement and disengagement of a clutch which are to be performed in a manual transmission by an actuator. For example, as is shown in FIGS. 8A and 8B, a gear change control system of an automatic transmission includes a shift shaft 100 which can move in a shifting direction sf and a selecting direction se, shift lugs 120 which are formed, respectively, at one parts on a plurality of shift rails 110 which are arranged in the selecting direction se, in such a manner as to project radially outwards therefrom and shift forks 131, 132, 133 which are connected integrally to another parts of the shift rails 110, respectively.
Furthermore, a control finger (an arm portion) 140 is provided on the shift shaft 100 in such a manner as to project radially therefrom, and a pair of claw portions 121 are formed on each shift lug 120 in such a manner as to be spaced apart from each other in the shifting direction sf.
In the mechanical automatic transmission configured as has been described above, by moving the shift shaft 100 by an actuator (not shown), the pair of claw portions 121 of one of the shift rails 110 are selectively moved in one or the other of the shifting directions sf by the control finger 140, so that the shift fork 131 which is linked with the shift rail 110 is made to shift a gear which faces oppositely the shift fork 131.
Incidentally, a dual-clutch automatic transmission has been developed in which two clutches are incorporated between an automatic transmission like the one described above and an engine which is a power source. This automatic transmission includes first and second main shafts, and one and the other of the main shafts change the speed of a rotational force transmitted thereto from the associated clutches for transmission to countershafts they face oppositely, the speed-changed rotation being then transmitted from each of the countershafts to an output gear side of the transmission. In the dual-clutch automatic transmission, in making a gear shift, a state in which one gear is engaged with one of the clutches via the first main shaft is switched to a state in which a target gear is engaged with the other clutch via the second main shaft, and as this occurs, a neutral state can be eliminated during the gear change by disengaging the one clutch while holding the engagement of the other clutch with the target gear, thereby making it possible to realize a smooth gear change without any interruption of power flow during the gear change.
In a gear change control system adopted in the transmission described above, for example, as is shown in FIG. 9A, it assumes that a gear change has been made from a fourth gear which is a gear currently engaged to a target gear, for example, a first gear while maintaining the state in which the current gear is engaged. Immediately thereafter, as is shown in FIG. 9B, while switching the engaged state of the clutch to the target gear side clutch is in progress, the gear shift made to the previously engaged gear (here, the fourth gear) is withdrawn therefrom. To describe this by reference to a locus indicated by a chain double-dashed line in the figure, in the gear shift withdrawal from the previous gear position, the following steps need to be implemented quickly: firstly, a step (1) in which the control finger is offset from the target gear (the first gear) position in the selecting direction, a shift step (2) in which the control finger returns to a neutral line N, a selecting step (3) in which the control finger moves towards the gear (the fourth gear), a shift step (4) in which the control finger moves towards the gear (the fourth gear), a selecting step (5) in which the control finger reaches the gear (the fourth gear) position, and a gear shift withdrawal step (6) in which the control finger withdraws the gear shift made to the gear (the fourth gear) to a neutral position (indicated by the chain double-dashed line) thereof.
In addition, JP-A-2001-304411 proposes an automatic transmission in which a pair of claw portions are provided on each shift lug in such a manner as to be spaced apart widely from each other in a shifting direction, so that a control finger can enter between the pair of claw portions on the shift lug of a target gear which is in a neutral state only by being moved in a selecting direction from between the pair of claw portions of the shift lug which is in the shifted state, so as to simplify the movement of a shift member.
In this way, in the dual-clutch automatic transmission, since the gear shift to the target gear and the gear shift withdrawal from the currently engaged gear need to be performed in that order during gear change, the movement of the control finger 140 gets complex, resulting in a cause for extending the gear change time, and an improvement in this area has been longed for.
Furthermore, in the related art disclosed in JP-A-2001-304411, in order for the arm portion (the control finger) of the shift member to enter between the pair of claw portions when the arm portion is moved directly in the selecting direction, the pairs of claw portions each have to be disposed in such a manner as to be spaced apart relatively widely from each other. In this case, as is shown in FIG. 7, in the event that an interval L1 between the pair of claw portions 121 is increased, the arm portion 140 of the shift member pushes on the claw portion 121 in such a state that the arm portion 140 is largely inclined in the shifting direction. As this occurs, it assumes that a force acting on the claw portion 121 by a rotational torque T of the control shaft 100 is a tangential force F, a distance from a contact point a between the arm portion 140 of the shift member and the claw portion 121 to an axial center C of the control shaft 100 is a distance L2, and an inclination angle of a line connecting the contact point a with the axial center C towards the shifting direction is an angle α, a component force of the tangential force F in the shifting direction, that is, a component force P1 which constitutes a force for moving the claw portion 121 in the shifting direction is obtained by the following expression (1).P1=F×COS α=(T/L2)×COS α  (1)
In the expression (1) above, it is found that with the distance L2 being substantially constant irrespective of the angle α, the component force P1 decreases as the angle α increases within a range of 0 to 90 degrees. In addition, it is found that the distance L2 increases and the component force P1 decreases further as the angle α increases within a range of 0 to 90 degrees. Consequently, in the event that the interval L1 between the pair of claw portions 121 is increased as with JP-A-2001-304411, the force P1 which pushes on the claw portion 121 in the shifting direction decreases, and it becomes difficult to move the shift lug which is linked with the claw portion 121 in the sifting direction with good efficiency.

Gear change control system of automatic transmission

Mitsubishi Jidosha Kogyo Kabushiki Kaisha


A multilayer component includes a ceramic base body and at least one internal electrode in the ceramic base body. The at least one internal electrode includes holes, and is made of a material having a liquidus temperature that differs from a sintering temperature of the ceramic base body. The ceramic base body is sinterable such that formation of holes in the at least one internal electrode occurs during sintering.

Inherent mechanical stiffness of multilayer components plays a key role in applications of such multilayer components, such as piezoelectric actuators and ferroelectric actuators.
WO 99/12865 describes a piezoelectric ceramic materials that includes lead zirconate titanate. For lead zirconate titanate with a perovskite structure A2+B4+O3, a desired stabilization of the materials is achieved through partial substitution with ferroelectrically active compounds. The sintering temperature of such components can thus be reduced.

Multi-layered component and method for the production thereof


A portable thermal oven includes a metal frame and a plurality of terracotta panels disposed inside of the frame and defining an enclosed chamber having a front panel, a rear panel, two opposite side panels, a top panel and a bottom panel. The furnace also includes a terracotta door hingedly disposed in the front panel and including a handle on one side thereof for opening and closing the door. A plurality of gas manifolds and a plurality of gas burners are disposed on each of the two opposite sides of the chamber and a ventilation hatch is disposed in the top panel for exhausting fumes and excess heat. A first and a second gas cylinder and pipes for connecting the gas cylinders to the manifolds for supplying gas and/or air to the manifolds are also provided.

Apparatus for making dental castings are well known and have been in use for many years. For example, a Emerick U.S. Pat. No. 4,150,707 discloses a method and apparatus for making dental castings. As disclosed, a method and apparatus for making dental castings wherein a crucible is supported on a platform having a central opening positioned beneath the crucible over a mold cavity of the investment, This in turn is supported on a platform having a central opening. The upper platform is lowered against the investment so that a single sealed vessel comprising the crucible and investment cavity is formed. Air is then administered to the crucible and investment cavity at a point beneath the crucible opening so that both the investment and crucible may be purged. An arc is formed in the crucible thereby melting the casting material, and air under pressure is admitted to the top of the crucible thereby causing the molten casting material to flow into the investment cavity.
An additional U.S. Pat. No. 4,497,658 of Woog discloses a compact precious metal furnace and recovery method. The Woog patent discloses a highly compact and efficient tilting crucible furnace and smelting method for use in the direct smelting of a precious metal containing material. A furnace body having a refactory lined cavity which has a top opening is pivotally mounted on a support frame to allow tipping thereof. A cover having a first opening to receive a gas burner and a second multi-purpose opening therein is rigidly attached to the body. A gas burner attached to the cover provides a downwardly directed oxidizing flame into the cavity to oxidize iron which is added to the cavity and other impurities in the precious metal containing material. A flux is provided to a thoroughly liquid mixture and after heating the molten mass is poured through the multi-purpose cover opening into a mold. As the mold cools, a doré button of precious metal settles to the bottom of the mold and slag containing impurities forms on the top.
A further Santilli U.S. Pat. No. 4,628,895 discloses a kiln and autonomous heat source portable integrated unit. As disclosed therein, the invention belongs to the technical field for equipment destined for hobby use and, in particular, relates to a portable kiln and heat source integrated unit. The disclosure envisages there being a combination of a portable kiln with a firemouth positioned at the bottom of the kiln; a support structure able to set the kiln in a removeable fit-lock way on a burner facing the firemouth and heat insulating means of protection designed to safeguard at least the elements placed adjacent to the firemouth.
Finally a more recent U.S. Patent of Hohenshelt et al., U.S. Pat. No. 7,458,809 discloses a portable kiln having a set of wheels, a handle and a platform base. The wheels and the handle are attached on a first side of the kiln so that the kiln can be tilted and rolled on the wheels using the handle. The platform base provides a spaced distance between the wheels and the floor when the kiln is sitting upright in an operational position. The kiln may also include a metal outer shell wrapped about an oven portion. The outer shell has a shell sidewall radially spaced from the oven portion sidewall which forms an annular air channel between the outer shell sidewall and the oven portion. The outer shell has a C-shaped cross-section and it has upper and lower vent openings for the air channel. A hinge assembly allows a lid of the kiln to rest in an open position.
Notwithstanding the above, it is presently believed that there is a need and a potential commercial market for an improved thermal oven in accordance with the present invention. There should be a need for such ovens because they are of simple design, rugged, portable and can be constructed at a reasonable cost. Such ovens are suitable for use by hobbyist or dentist to smelt relatively small amounts of gold or precious metals.


The present disclosure relates to a method for debugging in the formal verification of an integrated circuit design. The method may include providing, via a computing device, an electronic design associated with the integrated circuit. Embodiments may further include splitting one or more nets in a cone of influence of a target associated with the electronic design. For each split net, embodiments may include placing a constraint that re-joins the net. Embodiments may also include identifying a local region of the electronic design for which the target is unreachable. During formal verification, embodiments may include ignoring all constraints associated with the local region of the electronic design.

In general, it may be desirable to identify errors in semiconductor design while the semiconductor is in the design phase. As production moves from design to tooling and fabrication, the cost to fix design errors increases greatly. This great increase in cost may be attributable to specialized fabrication hardware that may have to be modified to repair a design error. A very small change in design can have cascading effects to other areas of the semiconductor. If these changes are made in while the semiconductor is in the design phase, software design tools can simply modify the architecture appropriately with little ramifications. If, however, a design error is found after production has transitioned to tooling and fabrication, a design change with cascading effects could necessitate the retooling of the entire line at considerable cost.
As design errors are much less costly to remedy while the semiconductor is in the design phase, much effort has been expended into methods of ensuring proper semiconductor designs in this stage. The process of ensuring proper design is referred to as verification. Design verification is generally focused into two areas: simulation and formal verification. Simulation involves testing the design against a sample set of inputs and checking the outputs against their expected values. Formal verification involves testing the universe of possible inputs against their expected outputs.

Method for debugging unreachable design targets detected by formal verification


A content addressable memory includes a priority encoder that is in communication with an array of the content addressable memory cells to receive match signals, and from the match signals generating an output index signal in accordance with a priority sequence of the match signals. The priority encoder has a plurality of input circuits to receive the match signals from the CAM array. A priority setting circuit receives a priority transformation signal indicating a priority index for modification of the priority sequence. An encoding circuit is in communication with the plurality of input circuits and the priority setting circuit for generating the output index signal in accordance with the priority sequence. The priority encoder circuit further includes an enabling circuit for receiving an enabling signal. The enabling circuit communicates the enabling signals to the encoding circuit, such that upon deactivation of the enabling signal, the encoding circuit generates the output signal in accordance with the priority sequence with no modification by the priority setting circuit. The priority index indicates a region of the content addressable memory exempted from effective comparison. This allows the CAM array to be searched for multiple matches of the comparand. The priority index thus is an index address of the content addressable memory determined with a previous search of the content addressable memory. The priority index is provided to the priority setting circuit through a word line decoder of the array of content addressable memory cells.

1. Field of the Invention
This invention relates to priority encoding circuits. More particularly, this invention relates to priority encoding circuits within a content addressable memory having a programmable priority index.
2. Description of Related Art
Content addressable memory (CAM) is well known in the art and is employed in applications such as "search engines" in bridge circuits of network routers. A message arrives at the bridge circuit and a destination address is extracted from the message. The address is compared to a database of addresses maintained in a CAM structure. When the address is found within the CAM, the CAM returns an index pointing to the appropriate link leaving the router. The message is then transferred on the link to the next router or the destination. The destination address may in fact match multiple entries within the CAM and for certain addresses or applications it may be desirable for the all the indices to be accessed.
Refer now to FIG. 1 for a discussion of the operation of a CAM of the conventional art. The CAM array 5 is composed of rows of CAM cells 10, which contains the data to be compared against. Each row of CAM cells 10 has an associated compare circuit 15 to simultaneously compare a comparand data 20 to the contents of each row of CAM cells 10. The comparand data 20 is transferred to all the comparators 15 through the bit lines 25 or other comparand lines (not shown) connected to the CAM cells 10 and the comparators 15 of the CAM array 5.
The result from each compare is indicated by the state of each of the match result lines 30. The "match line" passes through the CAM cells of the CAM array 5 along a row. The match lines feed into match line sense amplifiers to produce digital hit or miss indications. Only those match result lines 30 connected to the CAM cells 10 having comparison data matching the comparand data 20 are activated. The match result lines are the inputs to a priority encoder circuit 35. A priority encoder circuit, as is known in the art, provides an output containing a code indicating which of the input lines that are active based on a predetermined priority or precedence. In this circuit, the output lines 40 of the priority encoder 35 provide a Read Only Memory (ROM) address selection dependent on the match result lines 30 having the highest priority or precedence. Traditionally, this would indicate the address having the least magnitude. Obviously, other orders of precedence may be chosen. The output lines 40 of the priority encoder 35 are the address lines for the index ROM 45. The contents of the index ROM 45 are the indices pointing to the locations designated for the corresponding locations of the CAM array 5. The activate output line 40 of the priority encoder 35 causes the contents of the index ROM 45 to be placed at the match index output lines 50 of the index ROM 45. The match index 50 is then transferred to external circuitry for further processing.
The data contents of the rows of CAM cells 10 are written with the data being placed on the bit lines 25 just as the comparand 20 is driven active during a compare operation. The CAM array may include mask cells associated with the CAM cells 10. The mask cells and the associated CAM cells 10 comprise what is referred to as "ternary" CAM cells. A CAM array having only the CAM cells 10 is referred to as a "binary" CAM array. Upon placement of the data on the bit lines 25 or other comparand data lines (not shown), the address 55 is applied to the word line decoder 60. The word line decoder 60 interprets the address 55 to select the word line 65 attached to the row of CAM cells 10 into which the data may be written. If the row of CAM cells 10 includes mask cells, the cells may be masked to create a "don't care" state for those CAM cells.
Attendant with the memory data are flags indicating validity of the data, whether the data is to be ignored in the search, and other information regarding the data. These flags maybe physically part of the rows of memory cells 5 or separate in registers or random access memory (RAM) accessible with either the match lines or with the match index or with associated signals.
The ignore flag is used when all matches in the CAM array 5 to a comparand 20 are to be found. All of the matches for the comparand are identified and the resulting identification location transferred from the CAM array 5 by iteratively searching the CAM array 5. During the first iteration, the match having the highest precedence is identified and the ignore flag is set for the row of CAM cells 10 and a second search is performed and the next match with the next highest precedence is identified, since the match with the highest precedence is ignored. The process is repeated until all the matches within the CAM array 5 are identified. This process requires maintaining a listing of the match indices and from that listing setting the ignore flags and then resetting the ignore flags prior to a subsequent operation that is not a search with the same comparand. In some applications, it maybe desirable to allow searches for the presence of other comparands before determining the other matches for the original comparand. This forces the skip flags to be set and reset depending on which comparand 20 is being applied to the CAM array 5. The setting and resetting of the ignore flags cause extra processing and circuitry to maintain which of the rows of CAM cells 10 are to be ignored during particular searches.
U.S. Pat. No. 6,034,958 (Wicklund) describes an efficient approach to Asynchronous Transfer Mode (ATM) connection table lookup that minimizes the number of tables and memory lookups through the use of hash coding and binary table search techniques. The virtual connection information associated with an incoming ATM cell is hash coded. The hash code provides a compressed representation of the virtual connection information. This allows the address space of a table accessed based on the hash code to be much smaller than the maximum number of possible virtual connection combinations that can be encoded in the ATM cell header without restricting the set of possible virtual connection combinations. A binary search based on the cell's virtual connection information can be used to efficiently select, from plural records accessed based on the hash code, the particular search record corresponding to the cell's connection.

Circuit and method to allow searching beyond a designated address of a content addressable memory


A method for adjusting an optical axis of an optical disc drive. The method includes the following steps. A first reflecting member is disposed on a turntable of the optical disc drive, and is rotated along with the turntable. A laser light is emitted on the first reflecting member by a laser collimator, and a normal vector of the turntable is measured based on a light point reflected to the laser collimator from the first reflecting member. A second reflecting member and a third reflecting member are disposed on a guide bar of the optical disc drive. A first initial vector and a second initial vector are measured based on a light point reflected to the laser collimator from the second reflecting member and the third reflecting member. The guide bar is adjusted based on an oblique vector of an optical of an optical pickup of the optical disc drive, the normal vector of the turntable, the first initial vector, and the second initial vector so that the optical axis of the optical pickup is parallel to the normal vector of the turntable.

1. Field of the Invention
The invention relates to a method for adjusting an optical axis of an optical disc drive; in particular, to an adjusting method that can assist the optical disc drive in more accurately obtaining the data of an optical disc disposed thereon.
2. Description of the Related Art
Optical disc drives use light to transform information stored on an optical disc to a machine-readable format, e.g., binary data. Examples of optical disc drives are known in the art as compact disc drives (often referred to simply as CDs) and digital versatile disc drives (often referred to simply as DVDs). Some optical disc drives have the additional capability of being able to write data onto an optical disc by the use of a light source, e.g., a laser. Optical disc drives are used in various applications including music and video playing and recording devices and computer data storage devices.
When the data of an optical disc is obtained by the optical disc drive, an RF signal jitter transmitted from an optical pickup of the optical disc drive is proportional with an error rate. That is, when the jitter is greater, the error rate is also greater. Furthermore, when the jitter becomes too great, the data of the optical disc cannot be obtained by the optical disc drive. If the optical quality of the laser light, reflected to the optical pickup from the optical disc, is enhanced, the RF signal jitter can be inhibited. One manner of enhancing the optical quality is to allow the optical axis of the optical pickup (the laser light path emitted from the optical pickup) to be normal with the surface of the optical disc. Thus, the refractive loss and the diffusive loss of the laser light are decreased during reflection. As a result, in a conventional optical disc drive, a mechanism for adjusting its turntable or its guide bar is additionally disposed. Thus, a plane formed by the turntable or the guide bar can be adjusted to compensate the assembly error and the error of the optical axis of the optical pickup. Especially for DVDs, the effect of RF signal jitter due to the error of the optical disc drive is more apparent than that of CDs. Thus, the adjusting mechanism has become standard equipment in DVD players.
In a conventional process for manufacturing the optical disc drive, the optimal adjustment of the adjusting mechanism is determined based on the error rate or the value of the RF signal jitter obtained from the test disc. During adjustment, the lowest value of the error rate or the RF signal jitter is the optimal adjustment. However, among the factors that influence the error rate or the RF signal jitter, there are many factors other than the degree of inclination of the optical axis of the optical pickup, such as the quality of the optical disc or circuit noise. That is, the amount of inclination of the optical axis of the optical pickup is not the only factor. Thus, in the conventional adjusting process, the optimal adjustment is the optimal adjustment of the test disc, but not the optical axis of the optical pickup itself. That is, if the test disc is changed to retest the same optical disc drive, the position of the optimal adjustment is also changed. Furthermore, since the factors influencing the error rate and the RF signal jitter are complicated, the lowest value is difficult to judge. Thus, the optimal adjustment is also difficult to judge, and the time required for adjustment increases. As a result, the adjustment causes a bottleneck, and enhanced throughput is difficult to achieve.

Method for adjusting optical axis of optical disc drive


In one embodiment, a sample of an integrated circuit device is prepared for observation in a transmission electron microscope (TEM). The sample may be placed on a surface formed by vertical edges of several TEM grids. The sample may be affixed to a vertical edge of one of the TEM grids. The TEM grid supporting the sample may be separated from the other TEM grids, and then placed in the TEM so that the sample may be observed.

1. Field of the Invention
The present invention relates generally to integrated circuit fabrication, and more particularly but not exclusively to techniques for preparing samples for transmission electron microscope (TEM) analysis.
2. Description of the Background Art
Fabrication of an integrated circuit device often includes analyzing topographies at different stages of the manufacturing process to insure that the device meets specified functionality requirements. By topographies it is meant a substrate or wafer, such as a semiconductor wafer, having one or more layers formed thereon, regardless of whether a functioning device has been formed from the topography or not.
A number of different techniques may be used to analyze device topography. For example, a cross-sectional analysis of the device topography may be performed using a transmission electron microscope (TEM). Generally, a TEM directs an electron beam at a prepared cross-sectional sample of the device while a photograph is simultaneously taken. Both the photograph and electron beam are used to analyze the exposed layers.
There are several different techniques or approaches for preparing cross-sectional samples of a device for TEM observation and analysis.
In mechanical polishing, the sample is sandwiched between a glass slide and silicon, and then polished using a traditional wedge polish technique.
The focused ion beam (FIB) in-situ lift-out (INLO) method takes advantage of an FIB instrument's deposition and cutting capability to attach or detach the sample to either a probe or a grid. A specialized probe in the FIB instrument's chamber is employed to move the sample around. After the sample is transferred from an original grid to a vertical grid, the FIB instrument is used to cut the sample to form a thin area for TEM observation. Systems for preparing and manipulating TEM samples by the FIB INLO method are commercially available from Omniprobe, Inc. of Dallas, Tex. Further details of the FIB INLO method are described in, for example, T. Yaguchi, Microscopy and Microanalysis, Vol. 7, No. Supp/2, p. 938, 2001, and in K. Mcllwrath and N. Wang, ISTFA 2004, p. 320.
In the Glue+LO (lift-out) method, the sample is glued to silicon with conductive glue and, after the glue has cured, the FIB instrument is used to prepare the sample using a traditional lift-out technique. Typically, the sample is lifted out using glass needle. Further details of this method are described in, for example, Jon C. Lee, Microelectronics Reliability 41 (2001) 1551-1556.
Heretofore, the above approaches have not proven wholly satisfactory for a number of reasons. In particular, sample handling in the mechanical polishing method is extremely difficult and is highly dependent on the skill of the person doing the work. The FIB INLO method requires a focused ion beam (FIB) instrument with specialized probe attachments. Moreover, constant exposure to an ion beam may cause crystal structure damage to the sample, leading to erroneous analysis. Similarly, the Glue+LO method can cause sample crystal structure damage and sample loss during the lift-out. Furthermore, the particles in the glue can cause a non-uniform sample thickness, further complicating the analysis. Accordingly, there is a need for an improved technique of preparing and manipulating samples for TEM observation and analysis.

Preparation of integrated circuit device samples for observation and analysis


A method and apparatus for simultaneously measuring and calculating servo-related data is disclosed. The method involves measuring the servo related data for a first track of a disc drive and then measuring servo related data for a second track. The method further involves calculating servo related values for the first track, based on the measured servo related data for the first track, while servo related data is being measured for the second track. This method is applicable for processes such as zero acceleration path determination in disc drives, whereby position errors are measured for the first track and then position errors are measured for a second track while simultaneously calculating the zero acceleration path for the first track based on the position errors previously measured.

This application relates generally to servo control systems and more particularly to a method and apparatus that measures servo data for one track while calculating values for another track.
Disc drives have magnetic discs that are rotated while read and write heads communicate magnetic signals to and from the rotating disc. The magnetic signals are generally written in tracks that often form generally concentric circles about the magnetic disc. The tracks periodically contain servo related data, such as a track ID that indicates the track that the head is positioned over as well as position data that indicates the radial position of the head relative to other tracks and the centerline of the current track. Servo bursts are written into the magnetic disc during manufacturing and contain the servo related data.
A servo control system positions the head over the desired track and maintains that position during the read or write process for the desired track. The servo control system utilizes the servo related data to maintain the head""s position over the desired track by detecting that the head is straying from the centerline and by applying correction to the head""s position. However, the servo related data initially written during manufacturing may result in eccentricities, referred to as repeatable run out (RRO), due to various reasons such as spindle motor harmonics. Furthermore, the servo control system""s response may introduce additional eccentricity. As a result, the head follows tracks that are not ideally concentric.
The eccentricity of the tracks may create problems because one track may encroach upon another and data stored on the disc could become corrupt due to overwriting. Ideal track centerlines follow concentric paths that prevent such encroachment. Therefore, to establish the concentric path, a zero acceleration path (ZAP) is computed during certification of the disc drive. The ZAP process reads the servo data resulting in eccentricities and computes corrections that are written into the ID field of the track sectors for both the read heads and the write heads. These corrections instruct the servo control system to maintain the head such that generally concentric tracks result.
ZAP reduces the eccentricities but requires a relatively large amount of time to perform per disc drive being certified. Conventionally, ZAP is performed by reading servo data from a track, averaging position errors from an ideal center, and computing corrections based on the position error data. The corrections are then written into the ID fields for the track. This set of serial operations is repeated for each track and for each head.
Accordingly there is a need for a method that decreases the amount of time necessary for performing ZAP.
Against this backdrop the present invention has been developed. The present invention involves measuring servo data for one track while calculating the correction servo data for a previously measured track and then returning to the previously measured track to write the correction servo data. The time spent calculating for one track and measuring for another is thereby combined into the same time period to reduce the overall length of time require by ZAP.
An exemplary method for simultaneously measuring and calculating servo related data in a disc drive includes the following steps. A first servo related data is measured from a first track. Then, a second servo related data is measured from a second track. While performing the measuring step for the second track, a servo related value is calculated for the first track based on the first servo related data.
An exemplary disc drive configured to perform the exemplary method for simultaneously measuring and calculating servo related data includes the following elements. At least one head having a controllable position is included. The head is configured to perform the measuring steps of the method. A processor is included and is configured to receive servo related data from the head and to perform the calculating step of the method. A servo control is also included and is configured to control the position of the head.
These and various other features as well as advantages which characterize the present invention will be apparent from a reading of the following detailed description and a review of the associated drawings.

Method and apparatus for simultaneously measuring and calculating servo-related data


A tilt latch and pivot housing which has a collapsible retainer on each of its side walls extending along a substantial portion of the length thereof and angularly outwardly from the side walls of the housing. The inner surface of each retainer is spaced from the surface of the adjacent side wall of the housing, thus forming a crevice or gap designed to receive the retainer when sufficient pressure is applied to the retainer's outer surface causing the retainer to deflect inwardly. According to some embodiments, portions of the retainers adjacent to the upper engagement ends therof are beveled. The retainers may also be beveled on one end to facilitate installation of the housing into a sash. The housing may also include a collapsible retainer formed at the bottom wall of the housing for preventing longitudinal movement of the housing after installation. The present invention is also directed to methods of manufacturing sash windows having tilt latches and/or pivots incorporating the housings.

1. Field of the Invention
The subject invention relates to the field of window hardware, and specifically, to a tilt latch and pivot housing having outwardly projecting deflectable retainers that can be collapsed inwardly for installation in a sash window.
2. Background of the Related Art
A double-hung window assembly usually includes a window frame and a pair of window sashes mounted for reciprocal vertical movement. The window sashes are pivotally supported in the window frame. Vertical movement of the window sashes along the vertical slide channels formed in the jambs of the window frame is maintained by tilt latch mechanisms located at opposed corners of the window sashes. The latch mechanisms include latch bolts or sliders that can be moved along the slide channels and which, while engaged in the slide channels, prevent pivoting of the window sashes. When the latch bolt is retracted from the slide channel, the window sash can be pivoted on suitably installed pivot mechanisms. A pivot assembly for a sash window includes a rigid body and a pivot bar projecting from the body. Each pivot bar has an end adapted for being received in a brake assembly.
A sash window tilt latch usually includes a housing having an outward end opening, within which the bolt or slider is disposed. A spring contained in the housing forces the latch bolt through the outward end opening to engage the slide channels. A control knob is coupled to the latch bolt and extends upward through an elongated opening in the upper surface of the housing. The control knob permits selective inward movement of the latch bolt to release the latch bolt from the respective slide channel.
Sash window tilt latches can be surface mounted on the top rail portion of a sash, as shown, for example, in U.S. Pat. Nos. 4,837,975 and 4,901,475 to Harold Simpson, assigned to Ashland Products. Latches thus installed, however, are not considered aesthetically pleasing and have a tendency to fail due to repeated collisions with the header of the window frame. Accordingly, it has proved to be more advantageous to mount tilt latches substantially within the sash. Such flush-mounted tilt latches are disclosed, for example, in U.S. Pat. Nos. 4,553,353, 4,578,903, 4,622,778, and 4,791,756 to Harold Simpson, assigned to Ashland Products. The described latches, however, have complicated configurations and are relatively difficult to assemble.
U.S. Pat. Nos. 5,996,283 ("the '283 patent"), U.S. Pat. No. 5,970,656 ("the '656 patent"), and U.S. Pat. No. 5,829,196 ("the '196 patent") to Robert G. Maier, assigned to Ro-Mai Industries, Inc., U.S. Pat. No: 5,139,291 ("the '291 patent") to Steven E. Schultz, assigned to Ashland Products, and U.S. Pat. No. 5,671,958 ("the '958 patent") to Matthew P. Szapucki et al. describe tilt latch and/or pivot housings that can be more easily installed into sash windows. The housing described in the '291 patent has a side wall rail on each of its side walls. The installation of the housing into a suitably sized slot formed in a window sash is accomplished by inserting the housing longitudinally into the side opening of the slot so that the side wall rails are received in the matching cutouts in the side opening. Similarly, the pivot housing described in the '196 patent has a pair of channels, while the lower end of the sash is cut to define a pair of opposing rails. When the pivot housing is installed into the sash, the rails are received in the channels.
The '283 patent describes a tilt latch or a pivot housing assembly wherein protuberances are used in place of rail-shaped structures described in the '291 and the '196 patents for retaining the housing within the sash. The housing described in the '283 patent is installed into the sash by aligning the housing with the side opening of a slot cut in the sash and moving the housing longitudinally so that the edges of the slot are received in the gaps defined by the housing's flange and the protuberances on the side walls of the housing. Alternatively, the housing can be installed by aligning it with the top opening of a slot cut in the sash and then forced downwardly, so that the protuberances move past the edges of the slot and the edges are received in the gaps defined by the housing's flange and the protuberances.
The '656 patent describes a tilt latch or pivot housing having retainers along each of its sides that are capable of engaging the edges of a slot in a window sash, similar to the function performed by the protuberances described in the '283 patent. The retainers described in the '656 patent are flared upwardly and beveled rearwardly to facilitate their installation longitudinally or vertically.
The '958 patent describes a latch housing that snaps firmly into position when forced perpendicularly through an elongated opening in the top of a sash. The walls of the housing each have resilient tabs extending outwardly from the walls of the housing, that are pushed inwardly as the housing is forced through the elongated opening and snap outwardly to secure the housing within the sash. The tab's capability to be pushed inwardly is achieved by providing windows behind the tabs. The walls of the housing also have longitudinal slots for passing wings extending from a bolt disposed within the housing.
The prior art approaches to installation of a tilt latch or pivot housing into a window sash have various disadvantages that are overcome by the present invention. For example, a housing constructed according to the '291 or the '196 patent can be installed into a sash only from the side of the sash, while the housing of the present invention can be installed either from the side or from the top of the sash. Further, in the housing assemblies of the '291, the '196 and the '283 patents, the slots for receiving the housings are formed either by a single router in three steps or by two different routers. In contrast, when the housing according to the present invention is used, the matching slot in a sash can be formed in one step using a single router.
Finally, the '291, the '196, the '283 and the '656 patents all disclose retainers that are not movable with respect to the body of the housing. Therefore, when the housing is installed as shown in the '283 and in the '656 patents, the retainers (or protuberances) are likely to break off and the housing is likely to be deformed. This is avoided by the present invention through the use of a housing having retainers that can be deflected or collapsed inwardly. The housing having resilient tabs, as described in the '958 patent, also has various shortcomings that are improved in the housing according to the present disclosure. For example, the housing of the '958 patent has a longitudinal slot in each of the side walls, which leaves less space for the tabs, thus increasing the possibility that the tabs would break off during installation. Furthermore, due to their structural differences, the tabs of the '958 patent are less durable than the deflectable retainers of the present disclosure.
Accordingly, the present invention is directed to a tilt latch and a pivot housing having an outwardly projecting deflectable retainer on each of its walls, that can be collapsed inwardly for installation in a sash window, each retainer extending along a substantial portion of the length of the housing. The retainers may be beveled on one end to facilitate their installation.
The present invention is further directed to a tilt latch and a pivot housing that includes a bottom retainer or tab protruding from the bottom wall of the housing for engaging the inner surface of a sash. While the prior art discloses non-movable retaining tabs at the bases of tilt latch or pivot housings, the construction of the tab of the present invention is more advantageous due to its capability to retract during installation. Such construction helps avoid breaking off the tab and reduces deformation of the housing.
Finally, the present invention is directed to methods of manufacturing sash windows having tilt latches and/or pivots incorporating housings according to the present invention.

Sash mounted housing with collapsible retainers


Offset measurement and cancellation circuitry is employed in a transimpedance amplifier (TIA) circuit for directly measuring the offset in the TIA input voltage and for canceling the offset from the TIA output voltage. Employing the offset measurement and cancellation circuitry eliminates the need to use large transistors in the input stage of the TIA in order to reduce or eliminate the offset, which can increase noise and reduce Rx sensitivity. The offset measurement and cancellation circuitry of the invention obviate the need of making a tradeoff between the amount of noise and the magnitude of the offset that will be tolerated. The offset measurement and cancellation circuitry also eliminate the need for additional overhead in the decision threshold in order to avoid false triggering of the decision circuitry of the optical receiver due to noise.

A typical optical receiver (Rx) includes at least one photodiode that detects an optical signal and converts it into an electrical current signal and at least one transimpedance amplifier (TIA) that converts the electrical current signal into an electrical voltage signal. The photodetector, which is typically a P-intrinsic-N (PIN) photodiode, produces an electrical current signal in response to light detected by the photodetector. The TIA converts this electrical current signal into an output voltage signal having some gain, commonly referred to as transimpedance gain. This output voltage signal is further processed by other circuitry of the optical Rx (e.g., a limiting amplifier (LA), clock and data recover (CDR), etc.).
The output terminal of the photodiode is connected to the inverting input terminal of the TIA. Due to mismatch in the input stage and/or a systematic input bias voltage of the input stage, an input offset voltage is generated. The offset in the input voltage of the TIA results in an offset in the output voltage of the TIA. The common approach that is used to reduce or eliminate the offset is to use larger transistors in the input stage of the TIA. This approach, however, increases noise and therefore reduces the sensitivity of the optical Rx. Often, a tradeoff has to be made between the amount of noise that will be tolerated and the magnitude of the offset that will be tolerated. In addition, because the offset has a random nature, the offset output voltage together with noise can falsely trigger the decision circuitry of the Rx. For this reason, the decision threshold of the Rx is usually provided with some headroom to prevent noise from falsely triggering the decision circuitry of the Rx under worst case offset conditions.
In addition, applications with multi-mode or single-mode fibers may demand decreasing photodiode diameters to lower photodiode capacitances and therefore to improve sensitivity. As a result, the optimum noise figure achieved through noise matching is only possible if smaller transistors are used in the TIA. Furthermore, advancements in process technologies have also resulted in transistors having smaller gate areas, which in turn will result in even larger offsets.
Accordingly, a need exists for a way to eliminate or reduce the offset without increasing noise and/or without reducing the sensitivity of the Rx in which the TIA is employed.

Offset cancellation in a transimpedance amplifier (TIA) circuit

Avago Technologies General IP (Singapore) Pte. Ltd.


An RF transmitter includes a digital processor that includes a time shift signal determination block that produces a time shift signal based upon a bleed over power level in an adjacent channel resulting from downstream phase and magnitude mismatch of a primary signal. In one embodiment, the time shift signal determination block includes logic and circuitry for determining a power ratio for a primary signal between a bleed over power level in an adjacent channel and the primary channel. The time shift signal determination block produces the time shift signal to a time shift block that is operably coupled to receive one of an envelope magnitude component and a phase component from a digital signal generation block, wherein the time shift block generates a time shift in at least one of the envelope signal path and the phase signal path based upon the time shift signal.

1. Technical Field
The present invention relates to wireless communications and, more particularly, wideband wireless communication systems.
2. Related Art
Modern radio frequency (RF) transmitters for applications, such as cellular, personal, and satellite communications, employ digital modulation schemes, such as frequency shift keying (FSK) and phase shift keying (PSK), often in combination with Code Division Multiple Access (CDMA) communication. Some of these communication schemes, for example the 270.83 kbit/s binary Gaussian FSK employed in the GSM cellular telephony standard, have constant envelopes and the transmitter signal, sRF(t), may be represented mathematically assRF(t)=R cos(2πfct+θ(t)),   (1)where R denotes a constant amplitude, fc denotes the RF carrier frequency, and θ(t) denotes the information bearing part of the transmitted signal. An example transmitter appropriate for such constant-envelope modulation schemes is referred to as a translational loop transmitter. In this transmitter architecture, the digital baseband data enters a digital processor that performs the necessary pulse shaping and modulation to produce an intermediate frequency (IF) carrier fIF signal. The resulting digital signal is converted to analog using a digital-to-analog converter (DAC) and a low pass filter (LPF) that filters out undesired digital images of the IF signal. A phase locked loop (PLL)then translates, or shifts, the IF signal to the desired RF frequency channel and a power amplifier (PA) delivers the appropriate transmit power to the antenna.
According to related art, a radio transmitter includes a digital processor coupled to receive digital baseband data and produces a digital waveform characterized by an intermediate frequency and a phase. The output of the digital processor is produced to a DAC that is capable of processing intermediate frequency digital data while avoiding unnecessary quantization noise to produce an analog outgoing signal to a low pass filter. The low pass filter removes harmonics of the analog output of the DAC and produces an outgoing low pass filtered signal to a translational loop that up-converts the analog signal from an intermediate frequency to a radio frequency. The phase information originally produced by the digital processor is maintained in the RF signal produced by the translational loop to a power amplifier for amplification and radiation from an antenna.
The described radio transmitter is simplistic and is intended to represent various embodiments of RF transmitters, including embodiments in which the processing described occurs for both in-phase and quadrature phase signal paths (I and Q signal paths, respectively).
One typical radio transmitter used for GSM cellular telephony includes a digital processor that delivers a phase signal, θ(t), to the transmitter for further processing and RF transmission. The transmitter is typically a digital baseband processor that performs the necessary pulse shaping, modulation, and interpolation filtering, followed by in-phase and quadrature digital-to-analog converters, low pass reconstruction filters, and analog baseband mixers. A summing node combines the mixer outputs that are followed by low pass filtering. The remaining components of the transmitter are a phase and frequency detector (PFD), 26 MHz crystal reference (X-TAL), a charge pump (CP), a loop low pass filter (LOOP FILTER), a voltage controlled oscillator (VCO), a pair of offset mixers, as well as appropriate low pass filters. RF channel selection is achieved by employing a Fractional N frequency synthesizer. Within the translational loop, a sum of the mixing products of the baseband I & Q components is low pass filtered with down-converted RF output I & Q and is phase compared with a 26 MHz clock to generate a 26 MHz sinusoid whose excess phase component equals the difference between the desired baseband phase signal and the RF output phase signal. The 26 MHz carrier is extracted by the PFD whose output is the phase error signal.
With proper PLL design, the closed loop tracking action causes the error signal to approach zero; hence, the phase of the RF output carrier from a voltage controlled oscillator is produced at 900 MHz which tracks the phase of the baseband signal, as desired.
Other types of digital communication schemes, such as the 3π/8 offset, 8-level PSK employed in the EDGE cellular telephony standard, have non-constant envelope and the transmitter signal, sRF(t), can therefore be represented in quadrature form assRF(t)=i(t)cos(2πfct)+q(t)sin(2πfct),   (2)or, equivalently, in polar form assRF(t)=r(t)cos(2πfct+θ(t)),   (3)where both r(t) and θ(t) are information-bearing components of the transmitted signal. The signal components r(t) and θ(t) are referred to as the envelope and phase of sRF(t), respectively.
Transmitters in which a phase path is formed separate from an envelope path, as described above, are known as polar transmitters. One problem with polar transmitters, as will be described below, is delay mismatch between the phase and envelope components for the signals in the envelope and phase signal paths.
Delay mismatch may cause the translational loop output to be modulated by a time shifted envelope signal relative to the phase signal thereby causing an error in the transmitted RF signal. It should be noted that only delay mismatch between the envelope and phase signal paths has a detrimental effect on the transmitted signal. Any common delay along the envelope and phase signal paths does not affect the quality of the transmitted signal. One reason delay mismatch is problematic is that delay mismatch causes a phenomenon known as spectral re-growth, which results in an elevated power spectrum that may violate spectral mask requirements.
FIG. 1 is a diagram that illustrates delay mismatch between signals that are expected to be synchronous. In polar transmitters, for example, a phase signal component is desirably expected to arrive simultaneously with a phase signal to amplitude modulate the phase signal. FIG. 1, therefore, provides one example of a delay mismatch in which a phase signal is delayed relative to an envelope signal by a slight amount, shown as dt. For example, FIG. 1 may represent a phase signal that is delayed relative to an envelope signal in a polar transmitter by a value of 20 nano-seconds. Ideally, in a polar transmitter, such phase and envelope signals should be aligned for proper operation of the polar transmitter. One problem that is observable for such delay mismatch is that of spectral re-growth resulting in sustained spectral mask violations in adjacent channels.
FIG. 2 is a diagram that shows several example RF signal output power spectra corresponding to an Enhanced Data rate GSM Evolution (EDGE) signal with various delay mismatches between the envelope and phase signal paths of the RF polar transmitter. FIG. 2 illustrates values of adjacent channel power due to delay mismatch for adjacent channels 1, 2 and 3 (first, second and third adjacent channels) for frequency offset values of 0 Hz to 1 MHz. As may be seen in FIG. 2, the significant impact of delay mismatch, for example with a delay mismatch of 80 nS or greater, is that the spectral mask requirement of −54 dBc at 400 kHz offset is not satisfied. As may be seen, adjacent channels to a channel carrying a primary signal experience a corresponding spectral power growth or influence from delay mismatch in the primary channel. Such adjacent channel power growth due to a primary channel delay mismatch may be evaluated in terms of an Adjacent Channel Power Ratio (ACPR). Such channel power growth is undesirable because design/standards-based spectral mask requirements may be violated. In order to restore the RF transmitter performance, delay mismatch must therefore be substantially canceled or reduced to reduce a value of ACPR if the ratio is calculated with the adjacent channel power in the numerator and the primary channel power in the denominator of the ratio. The delay mismatch may be reduced or canceled by introducing one of a positive or negative delay of a signal in one of the paths.
It is clear from the foregoing description of the related art, that a method and an apparatus are needed that addresses the problems of delay mismatch and that finds a method for minimizing adjacent channel power ratios as defined herein while adhering to spectral mask requirements to improve performance of polar transmitters that are presently being designed.

Digital algorithm for on-line ACPR optimization in polar RF transmitters


A circuit for initializing a D-latch of an input/output system. The circuit comprises first and second logic means, the first logic means generating an enable signal coupled to the clock input of the D-latch which changes state from inactive to active at a first time t1 and again at a subsequent time t2, in response to the system write control signal addressed to the D-latch and the system reset signal. The second logic means generates a local data signal, in response to the system reset signal and system data signal, to the data input of the D-latch. The D-latch is reset substantially at time t1 and the system data signal is strobed in the D-latch substantially at time t2.

In most modern computer systems, the input or output device is typically controlled by a central processing unit through an input/output controller. For instance, FIG. 1 shows how an output device, such as a monitor 5, is controlled by a central processing unit (CPU) 1.
In FIG. 1, video controller 2 and screen random access memory (RAM) 3 are coupled to the CPU 1 through address, data and control buses 6. The CPU sends to the screen RAM 3 data to be displayed The screen RAM 3 receives the address and data signals from the CPU 1 so that the CPU 1 can change the screen image as expected. The CPU sends control signals and some basic display parameter data signals to the video controller 2 to control the display of the monitor 5. The video controller 2 operates in accordance with the commands of the CPU 1 and, through the address, control and data buses 10, causes the data signal 8 of the screen RAM 3 to be transmitted to processing logic 4. The processing logic 4 is controlled by the control signal 7, such as horizontal synchronize and vertical synchronize signals, from the video controller 2. The monitor 5 receives the data signals 9 from the processing logic 4 and displays the data as a result of the control signal 7. Furthermore, if the screen RAM 3 is a dynamic random access memory (DRAM), the video controller 2 also refreshes the DRAM through the buses 10 to keep intact the stored data in the screen RAM 3.
The video controller 2 includes at least a plurality of registers that must be initialized by the CPU 1. The CPU 1 communicates with the registers through the data bus. These registers hold basic system parameters such as the number of horizontal lines for each character row, number of lines per field, the cursor location, and whether interlaced or non interlaced scan is desired, etc. These default values of the parameters are written into the registers of the video controller 2 by the CPU 1 after the completion of the reset step of the system. If the user of the system desires a display mode different from that of the default values, he may input the desired values of the parameter into the registers to change the display mode. These parameters control the operation of the video controller 2, thus making it produce the desired screen display on the monitor 5. More detailed descriptions of the video controller may be found in the book of Gerry Kane, CRT Controller Handbook, Osborne/McGraw-Hill, Berkeley, Calif, 1980.
For some other input/output controllers which have several modes of operation, the particular mode in use at any time is also determined at least by the bits in a command or status register which is included in the input/output controller. The command register is written to by the CPU, so that the CPU can command the input/output controller to operate in a given mode, and the CPU can change these commands as the program progresses. The status register is written into by an external device. It contains the information about the status of the external device such as if the printer is out of paper, if the tape drive needs another character, and so on. The CPU can read the status register to monitor the progress of data transfers and take appropriate action when required. A complete discussion on the peripheral interface controller can be found in the book, "Using Microprocessors and Microcomputers: The 6800 Family" by Greenfield and Wray, Wiley, N.Y., 1981.
In general, the above described input/output registers of the input/output controller are first reset after the power-on of the system. In most cases, the CPU generates a RESET signal to each bit of the registers while resetting. The input/output controller needs this reset step to function as expected. Afterwards, the CPU writes the default value into the input/output register to begin a default mode of operation of the input/output device. The input/output register may contain 1 bit or more of bits, depending on the requirement and complexity of the system.
In general, the input/output register is made of flip-flops and each bit of the register contains one flip-flop. In conventional design, the D type flip-flop (D-FF) with reset shown in FIG. 2 is implemented in the registers of the input/output controller. The operation of a D-FF with reset may be found in any digital design literature. The timing of the signals in FIG. 2 may be found in FIG. 4. In FIG. 2, the Clock (C) pin is connected to the system write signal XWJ which in our example is an active low signal. The D pin is connected to the system DATA signal. The reset pin is connected to the RESET signal which is generated from the electronic data processing system. In our example the system reset signal RESET is active low. The QQ output is low during the time RESET signal is low for reset purpose and remains low afterwards until the positive-going edge of the system write XWJ signal, at which time the data is strobed in and then latched by the D-FF.
In the prior art, each different input/output device, in general, has its own input/output controller in form of an integrated circuit(IC). However, it has been a recent trend that all input/output controller circuits are integrated on a single integrated circuit to miniaturize the data processing system. This is sometimes called the super input/output controller system. Since all input/output controller systems have been integrated on a single integrated circuit, it is not surprising that there may be several hundred of the above mentioned input/output registers. This results, on the average, in several thousand D-FF's with reset on a single integrated circuit. Therefore, a substantial amount of cell area is occupied by the input/output registers.
It is therefore one objective of the instant invention to reduce the chip cell area occupied by the input/output registers by providing a control circuit together with the implementation of a D-latch instead of the conventional D-FF with reset.

Circuit for initializing registers using two input signals for writing default value into D-latch after a reset operation


A multistage transmission with a drive shaft (3) is connected with a shiftable primary planetary gear set (10), having an output shaft (4), connected with a shiftable principal planetary gear set (20) and being provided with a plurality of shifting elements (A to F), via selective closings of at least six forward gear stages, without group shifting, can be attained. One output element of the primary planetary gear set (10), via a first shifting element (A), can be connected with a first input element of the principal planetary gear set (20) and via a second shifting element (B) can be connected with a second input element of the principal planetary gear set (20). The input drive shaft (3) is, via a fifth shifting element (E), connectable with a third input element of the principal planetary gear set (20). Advantageously, a sun gear (11) of the primary planetary gear set (10) is fixed in location, via a sixth shiftable element placed on that side of the primary planetary gear set (10) which is remote from the principal planetary gear set (20). The primary planetary gear set (10) is designed as a plus-transmission with inner and outer planet gears (12, 13), the spiders thereof being bound together.

In U.S. Pat. No. 5,106,352 A, there is made known a plurality of schematic drawings and descriptions for automatic transmissions with one non-shiftable primary gear set followed by one after gear set, with which, by selective closure of five shifting elements, six forward gear stages can be achieved without group shifting. The after gear set is designed as a shiftable two-spider, four shaft, gear train with two connected planetary gear sets. The non-shiftable primary gear set can be built as a single spider planetary gear set or alternately as a forward power transmission means with two spur-gear pairs of differently determined ratios, which operate as a reducing gear train. One element of the primary gear set is bound securely to the transmission housing. The primary gear set is driven at the input speed of rotation of the transmission and produces a reduced output rotational speed. This reduced output rotational speed is transferred by two shifting elements to two different elements of the after gear set. Additionally, a third element of the after gear set can be directly driven by an additional clutch at the transmission input speed of rotation.
A six-gear stage automatic transmission 6HP26, which is derived by the applicant according to a concept from U.S. Pat. No. 5,106,352 A is described in, Prof. Dr. P. Tenberg: E-Automat—Automatic Transmission with Esprit, VDI Report No. 1610, 2001, pages 455 to 479. Relying on the basis of this report, Prof. Dr. Tenberg proposes to design the sun gear of the originally non shiftable, primary planetary gear set, to be actually shiftable by means of an additional brake. When this is accomplished, then, the now shiftable primary planetary gear set is designed, unchanged, as a so-called "minus-gearing", the internal gear of which is driven at the input drive shaft speed of rotation and the spider thereof forms its output element. In regard to the "minus transmission", what is to be understood is a simple planetary gear set with a negative fixed gear ratio. The ratio of the speeds of rotation of the internal gear and the sun gear, when the planet gear holder is fixed, is negative. The additional brake can be employed as an integral startup shifting element in the transmission. In accordance with corresponding toothing design, even seven forward stages can be provided, with a gear spread equivalent to that of a basic transmission, disadvantaged however, with an unfavorable succession of gear stages.
U.S. Pat. No. 3,941,013 A discloses a gear train schematic of an automatic transmission, with six forward stages. This transmission has one primary gear set designed as a single spider planetary gear set and one drive gear train consisting of two single spider planetary gear sets coupled together. Two of the three input elements of the second drive gear sets are, in this arrangement, connected together. The primary gear set is designed as a so-called "plus gear drive" with double planetary gear sets, the spiders of which are connected together and operate up to the sixth stage, in which it then revolves as a piece, serving as a reducing gear set. As far as "plus gear drive" is concerned, what is meant thereby is a simple planetary transmission with a positive fixed gear ratio. Further, the ratio of the speed of rotation of the internal gear and the sun gear is also positive during the imagined fixed spider. The sun gear of the primary gear is immobilized by means of a brake abutting the transmission housing. This brake is set spatially between the primary gear set and the after gear train. The primary gear set is driven at the speed of rotation of the input drive shaft by means of its coupled spider, its output drive is executed by means of the internal gear. The output speed of rotation of the following gear set can be transmitted by two clutches onto two different input elements of the following gear set, whereby these two different input elements of the following gear set, together with an additional clutch can be directly connected to run at the transmission input drive shaft speed of rotation. This additional clutch is placed on that side of the primary gear set which is remote from the subsequent gear set. Because of spatial positioning of the brake, by means of which the sun gear of the primary gear set is fixed, and the spatial placement of the clutch, by means of which the transmission input speed of rotation can transferred to the following gear set, a guide for input drive and output drive of the primary gearing is created. In this way, the torque of the primary gear set is directed outwardly and radially by its internal gear. That is to say, the drive of the primary gear set completely encompasses it. Further, the output drive of the primary gear set is directed centrally through the sun gear of the primary gear set to the input elements which are constructed as external disk carriers of the two clutches. The gear set concept of the U.S. Pat. No. 3,941,013 A additionally requires several group shiftings for the shifting of the six forward stages.
Thus, the purpose of the invention is to develop further, from the cited state of the technology, a multistage transmission, with at least six forward gear stages, without group shifting, wherein, one shifting element of the multistage transmission is to be an integrated startup shifting element, wherein the whole is made without excessive expense in construction, with a favorable stage succession, and an increased gear spread.


An intraocular lens system comprising at least one intraocular lens having an anterior surface and a posterior surface, wherein at least one surface of the lens is aspherical to provide for a continuum of retinal images to be focused at the retina in an area between two retinal eccentricities. The system may include an anterior light-converging intraocular lens 16 for positioning within the eye, the anterior lens having an anterior surface and a posterior surface; and a posterior light-diverging intraocular lens 17 for positioning within the eye posterior to the anterior lens, the posterior lens having an anterior surface and a posterior surface; wherein one or both surfaces of the anterior lens and/or one or both surfaces of the posterior lens are aspherical.

The most common condition affecting the macula is age-related macular degeneration (AMD)—this is also the most common cause of significant visual loss in the developed world. AMD results in loss of the light-sensitive cells (photoreceptors), and supporting tissue at the back of the eye, in a specialised part of the retina known as the macula. The condition most often involves the very central part of the macula (the fovea), an area which enables reading and the recognition of faces. In the majority of patients with age-related macular degeneration loss of vision occurs over a number of years and the pattern of visual loss allows for the maintenance of small islands of functioning photoreceptors in the macula. These remaining islands of tissue may permit sufferers to read but, because the density of light-sensitive cells reduces with increasing eccentricity from the fovea, visual resolution may be impaired such that at 3 degrees nasal to the central fovea, the visual acuity is reduced to 0.4 (compared with a visual acuity of 1.0 at 0 degrees), and at 5 degrees the visual acuity is further reduced to 0.34. Depending on the severity of the disease, patients may benefit from visual aids such as magnifying glasses, or the use of spectacle-mounted or hand-held telescopic devices that facilitate reading. Use of such devices is often restrictive because magnifying glasses are not easily portable (and require good lighting), and telescopic devices can severely reduce a patient's field of view. Despite the problems associated with reduced visual resolution, patients with age-related macular degeneration and similar conditions affecting the central visual field may still make effective use of residual macular tissue outside the damaged fovea (sometimes referred to as the 'preferred retinal locus' or PRL) although this may require the patient to learn to fixate eccentrically—something that is not always easily accomplished. One potential method of improving patients' fixation is to undertake surgery to introduce a device to modify the path of light in the eye such that images are focused on the PRL with or without a magnifying effect. However, the precise location of the PRL varies from patient-to-patient and accurate targeting of the PRL using such an approach is essential if a patient's vision is not to be made worse. Furthermore, as the disease progresses and remaining islands of functioning retina shrink in size, the location of the PRL can shift and it may become necessary to alter the path of light in the eye to take account of this.
Current surgical approaches to the management of poor vision in age-related macular degeneration include the implantation of telescopic lenses, in some cases not dissimilar to those employed for use in cataract surgery. Such lenses have the advantage of superior optics without the disadvantages associated with the use of external telescopic devices. Furthermore, telescopic devices may be configured in such a way as to provide a magnified image that is focused on an area of healthy macula eccentric to the fovea. Most existing designs for these intraocular devices adopt variations on a Galilean telescope system such that a diverging intraocular lens (IOL) is sited in the eye behind a converging IOL.
A basic paraxial approach to an intraocular Galilean telescope is as follows:
                                                        D              =                                                f                  obj                                +                                  f                  oc                                                                                M              =                              -                                                      f                    oc                                                        f                    obj                                                                                }        ⟶                                                      f              obf                        =                          D                                            M                                  M                  -                  1                                                                                f              oc                        =                          D                                                              -                  1                                                  M                  -                  1                                                                          }D=distance between lenses (assumed thin lenses)M=magnificationfobj=focal length of the objective lensfoc=focal length of the ocular lensGalilean intraocular telescopes that employ a light-diverging IOL located in the posterior chamber of the eye and a light-converging lens in the anterior chamber of the eye are disclosed by Orzalesi et al. (Ophthalmology Volume 114 Issue 5; 2007) and in U.S. Pat. No. 20120136438 A1. These systems provide for magnification of an image and the deviation of light to target healthier parts of the macula. The latter is achieved by displacement of the diverging lens in a direction perpendicular to the optic axis of the converging lens by means of an asymmetrical haptic design (the haptic is the supporting arm of an IOL, most often seen in pairs with each one attached at opposite sides of the implant to ensure the position of the IOL in the eye remains stable). By shortening one haptic and lengthening the other it is possible to shift the diverging IOL such that a prismatic effect is achieved and light focused eccentric to fixation. The arrangement has a number of disadvantages. Firstly, the prismatic effect is conferred by the diverging IOL, which lies behind the converging IOL in both instances, thereby making access difficult for the purpose of rotating the diverging IOL to target the PRL should its location change at a future date. Secondly, the siting of an IOL in the anterior chamber is known to be associated with secondary pathology such as glaucoma and damage to the cornea of the eye. Thirdly, the optics of such a configuration are highly dependent on the IOLs remaining a fixed distance apart, for the purposes of magnification, and at a fixed displacement perpendicular to the optical axis (in the case of the diverging lens) for the purposes of targeting the PRL so that without consideration of the optimal configuration of the IOLs in relation to one another the system has the potential to make a patient's vision even worse.
Intraocular telescopes that take advantage of IOLs placed in fixed alignment are disclosed in U.S. Pat. Nos. 7,186,266; 6,596,026; 5,391,202; 7,918,886; 20040082995 and 20110153014. The principal disadvantages of fixing the diverging lens to the converging lens in these systems are that: 1) The arrangement may not permit the displacement of one lens in relation to the other to create the prismatic effect necessary to target the PRL (as is the case with most cylindrical one-piece designs); 2) in some instances, the prismatic effect, if achieved, may not be modifiable without replacing the implant; 3) in the case of systems where the device (or part of the device) is implanted in the capsular bag, fibrosis of the capsular bag over the implant may prevent its easy replacement or rotation should the need arise for adjustment in response to a change in the PRL; 4) the size of the implant is increased such that a larger incision in the eye is required to site it (this is associated with longer wound-healing time and increased astigmatism that may adversely affect the quality of vision). In addition the high dioptric power of the lenses employed requires careful consideration of the lens surfaces so as to optimise visual potential and avoid poor performance of the implant.
Consequently there exists the need for an intraocular lens system that reliably focuses an image on the PRL, whilst also being flexible enough to allow for changes in the location of the patient's PRL without the need for further surgery.


The invention provides systems and methods for implementation of a computer language type system by augmenting finite state automata algorithms to accommodate symbols having both subtype relationships and nested types. To make the classical automata algorithms work for type system with subtypes, finite state automata for a data type is augmented by additional transitions that include secondary symbols, wherein secondary symbols are subtypes of symbols of alphabet of finite state automata. A data type when compared to another data type must compare both names and the contents.

Types are used by programming languages to determine whether a particular data is in a particular form. Conventional programming languages define type systems having types such as integer, string, etc., and user-defined structures. XQuery is a programming language that defines a rich and complicated type system. XQuery is a language for querying XML documents. In addition to types found in conventional programming languages, the type system of languages like XQuery allows new types to be created using sequences (e.g., integer followed by string), alteration (e.g., integer or string), shuffle-product (e.g., integer and string in either order), and occurrences of those (zero or one, zero or more, and one or more).
Types are used by XQuery to determine whether XML data is in the required form. To determine the type of a XML data for atomic types, an XQuery processor can use a class hierarchy to model the type hierarchy as defined in the XQuery specification. For example, the built in or atomic types like xs:integer, xs:boolean, xs:date, etc. can be represented by singleton instances of classes comprising an inheritance hierarchy. FIG. 1 shows such a declaration for an abstract base class XQueryAtomicType with some details of method and data members. Complex types can be created from atomic types. For example XQuery allows complex types to be created from atomic types using sequences, alternation, shuffle-product, occurrences etc. Determining complex types requires type system answering questions like: "If two types are equal?", "Is one type a subset of another?", "Do two types intersect?" etc. Using the class hierarchy, it is not sufficient to answer the questions needed to determine complex types.

Systems and methods for implementing a computer language type system