The invention notably relates to a computer-implemented method for selecting an appropriate decision by constraining options assessed with a model. The method comprises selecting a model capable of receiving inputs and providing output in response to an input; training a model with a set of data representing similar events; generating options that represent hypothetical events; computing target values by applying the trained model on the generated options; computing index for indexing the generated options and target values associated with the trained model; querying the said index for obtaining a selection of a set of options, the selection being performed according to a specific constraint; returning, as a result of the query, a subset of the set of the generated options, the subset being ranked according to the target values associated with each option.

Recommendations are used for decision making in engineering. For instance, in an ongoing satellite launch, recommending emergency actions is needed to minimize a function of the risk of incidents (e.g. controlling the temperature of the fuel tanks, fuel consumption, speed of the launcher . . . ) Recommendations are not limited to the control of a device, but they can also be used during the conception and the manufacturing of a device, e.g. a CAD system may provide recommendations during the design of a device so that the risk of malfunctioning of the designed device is minimized.
There are several known categories of recommendation systems. A first category comprises the so-called recommender systems that are systems in which a visitor receives content suggestions based on the contents already visited. For instance, a search engine ranks search results based on personal history of pages visited. Examples of such systems are discussed in Balabanović, Marko, and Yoav Shoham. "Fab: content-based collaborative recommendation." Communications of the ACM 40.3 (1997): 66-72, or also in Sarwar, Badrul, et al. "Item-based collaborative filtering recommendation algorithms." Proceedings of the 10th international conference on World Wide Web. ACM, 2001.
However, these recommender systems work in applications that centralize the history of a large number of users. For example Google© search has more than 1 billion users. Systems that are hosted on the server of a company do not have such a pool of decision-makers to learn from. Decision-makers typically use best business practice or management consulting firms for advice based on accumulated experience of their peers in similar situations. But the relative isolation of business, operational and equipment data from different companies make it difficult to automate this learning process by computer programs. So rather than looking at the history of decisions from their peers, decision-makers assess situations based on data descriptive of the situation that triggers the need for a decision (variables descriptive of their own operations and equipment for instance). Therefore, these recommender systems are not suited for these situations.
A second category comprises the rule based systems that automate decision making related to certain problems. Based on rules written by experts are applied automatically. When the number of options is small and the input variables are manageable by a person, or processed to be summarized in a manageable set of discriminative variables, then it is possible for an expert to specify rules that will produce the optimal action in most cases. The first approach is called "expert rules only" wherein the rules are manually written by an expert of the technical filed on which the system will be applied. The second approach is called "expert rules combined with empirical models" in which an empirical model is built based on machine learning to process the available inputs and return a manageable number of inputs. Such models would typically return an estimated probability. The room for human error is reduced because the complexity of the inputs provided to human-written rules is reduced.
However, this second category suffers many drawbacks; notably, the two approaches do not work when the number of independent factors and the number of options lead to a problem not manageable by a human expert. An approach of the type «expert rules only» will not entirely capture the contribution of all input variables, and an approach of the type «expert rules combined with empirical models» will either lead to an incomplete empirical model (if all independent factors are not represented in the input variables) or lead to a model not understandable by a human expert. A human expert who does not understand the model will not be able to assess its relevance in presence of new information that did not exist or was not taken into account when training the model.
An example of empirical models, include the empirical rule generation systems such as Delmia OI©. These systems illustrate the complexity required to handle such phenomena. Empirical rule generation systems model phenomena described by large numbers of variables. They work by producing many rules with individually low recall and low precision, and therefore potentially mutually contradictory, resolving their different outcomes with a vote, and outputting the result of the vote, which is used as a new synthetic variable to describe the situation. These systems typically achieve simultaneously high recall and high precision (above 80% each) but to do so, produce an unmanageable number of rules (to the order of tens of thousands to millions for a few dozen variables) that could not have been produced by experts.
Such systems can be successfully used in approach "expert rules combined with empirical models", except as to providing a model that an expert can fully understand in cases with many input parameters and a relatively small number of options.
However, such empirical models do not let decision-makers take into account data that did not exist or was not taken into account when training the systems and writing the expert rules. In addition, empirical models require substantial hardware resources to train. In practice the need for decisions is typically triggered by new data. And decisions typically have to be taken quickly. Thus further restraining the amount of resources available and the number of cases where these systems can be used.
A third category comprises understandable models, representations and interactive interfaces that help make decisions, by presenting the relevant information in a form that makes it manageable by the decision-makers or their aids. For instance, Business Intelligence tools provide means to select variables and visualize their interactions for instance by way of scatter plots. Analysts pick relevant visualizations, produce static reports and send them to decision-makers.
The so-called "Whitebox models" rely on empirical (trained) model giving a visualization or explanation of the relationships between the variables. For instance, after training decision trees (as discussed for example in Quinlan, J. Ross. "Induction of decision trees." Machine learning 1.1 (1986): 81-106. [1]), rules building engine, or bayesian networks (as discussed for example in Heckerman, David, Dan Geiger, and David M. Chickering. "Learning Bayesian networks: The combination of knowledge and statistical data." Machine learning 20.3 (1995): 197-243), it is possible to understand the rules that, with some probability, link a target variable to a number of premises among the variables that describe the phenomenon.
When input data can be represented in a graph, techniques exist to map the graph into a 2-dimensional drawing in such a way that the distance between two entities on the 2D map is representative of their connectivity in the graph. These techniques allow to qualitatively represent the degree of interaction between elements descriptive of the situation. These techniques can also be applied to map complex observations on a 2D map so that similar observations (close in N dimensions, where the dimensions are the variables descriptive of the observations) end up close to one another on the 2D map, as discussed for example in Balasubramanian, Mukund, and Eric L. Schwartz. "The isomap algorithm and topological stability." Science 295.5552 (2002): 7-7.
Clustering techniques are discussed in Jain, Anil K., M. Narasimha Murty, and Patrick J. Flynn. "Data clustering: a review." ACM computing surveys (CSUR) 31.3 (1999): 264-323 and these clustering techniques allow to group together in a manageable number of groups observations that are similar in N dimensions.
Dimension reduction techniques are discussed in Wall, Michael E., Andreas Rechtsteiner, and Luis M. Rocha. "Singular value decomposition and principal component analysis." A practical approach to microarray data analysis. Springer US, 2003. 91-109, and they allow finding of the dimensions, or combination of dimensions, along which data varies the most.
Other techniques exist to find what dimensions (descriptive variables) have the highest impact on the value of a given target variable.
However, the "Whitebox models" suffer several drawback. Notably, these systems still do not provide fully automated decisions and therefore allow for suboptimal decisions due to human error such as omission of an important factor or inaccurate estimate of the actual impact of the factors taken into account.
Within this context, there is still a need for an improved method for selecting appropriate decisions by constraining possible options assessed with the help of a machine learning model.

Recommendations based on predictive model


A dual-fuel integrated switch includes a bracket. A valve body is provided on one side of the bracket. The inside of the valve body is provided with a spool adapted to the valve body. The spool rotates in the valve body. The first flow passage and the second flow passage communicating with the first flow passage are provided in the spool, an arc-shaped groove is provided on the outer wall of the spool, and the third flow passage adapted to the groove is provided on the side wall of the valve body. The number of the third flow passages is two, and the arc formed by the third flow passage on the side wall of the valve body is the same as the arc at the outer end of the side wall of the groove.

At present, small engines powered by gasoline, diesel, natural gas, liquefied gas and the like and electrical equipment driven by them mainly provide temporary power, mobile power and special machinery in the fields such as hospitals, hotels, homes, urban construction, and environmental protection. In recent years, with the increasing popularity of camping and adventure in the wild, small engines also provide temporary power for such activities.
The fuel switching switch, choke switch and flameout switch in the existing dual-fuel engines are generally separately provided. When starting the engine, first select the fuel to be used, then close the choke valve, and manually or electrically start the engine after turning on the fuel switch; after the engine is started, it is necessary to open the choke valve in time to make the engine run stably; when turning off the engine, it is necessary to press the flameout switch and fuel switch. This method is cumbersome and inefficient, and when the user forgets to turn off the fuel switch and the two fuels enter the engine at the same time, there are potential risks such as fuel leakage, engine damage and fire. For example, the Chinese utility model patent (application number: 201720170608.8) discloses a combined control switch for dual-fuel engine, which comprises a knob for controlling the state of the engine; a dial assembly, including a dial and a lever, and the lever is fixedly arranged on the dial; a first rotary member, the lever is in contact with the first rotary member to push the first rotary member to rotate; a second rotary member, the lever is in contact with the second rotary member to push the second rotary member to rotate; a fuel switch and a gas switch; the first rotary member drives the fuel switch to turn on, or the second rotary member drives the gas switch to turn on. The combined control switch described in the said patent has a complicated structure, and the gas switch and the fuel switch are separately provided, which increases the production cost of the product.


A method for determining the displacement in six degrees of freedom of a rectangular planar surface with respect to a reference position includes providing a reference image having projections of a defined lighting pattern having at least six points on a reference rectangular planar surface in the reference position, the six points including first, second and third points on the reference surface, fourth and fifth points at the intersections of a first edge of the reference surface, and, respectively, first and second parallel lines in the plane of the reference surface and perpendicular to the first edge, and a sixth point at the intersection of a second edge of the reference surface and a third line in the plane of the reference surface and perpendicular to the second edge, the first edge being perpendicular to the second edge, and the first and second points being in known relationship with the first, second and third lines. The method further includes the step of obtaining a real image including the projection of the lighting pattern on the surface, and determining the displacement of the surface with respect to the reference position from the positions of the six points in the reference image and the real image.

This invention relates to machine vision systems, and in particular to machine vision systems having application in the handling of packages.
In the shipment of parcels and packages, large truck trailers and the like must be loaded at a hub or sorting facility with a large number of packages. Conventionally, the majority of packages are parallelepipeds. Thus, such packages can conveniently be stacked in loading trailers. Such loading of trailers is conventionally accomplished manually. However, manual loading suffers from the disadvantages that the packages are frequently manually stacked in an unstable manner which may result in package shifting in transit and resulting damage. In addition, when packages are manually stacked, the space utilization within the trailer is ordinarily inefficient.
It has thus been proposed that an automated system be developed for stacking of packages within a trailer. Such an automated system would desirably include an apparatus to measure the weight and size of each package and, through appropriate algorithmic techniques, select a location on a stack for placement of each package with a high degree of stability and efficient utilization of space. Upon determination of a location, a robotic arm and gripper or hand, provided in the automated system, would place the package in the selected location.
A feedback system is required to determine whether each package, once placed by the gripper is in fact in the selected location. Such feedback information is required to avoid package collision in subsequent stacking. Machine vision systems might provide such a feedback system. However, any feedback system must determine in real time whether each package is placed properly. Thus, calculations of whether the package is properly placed must take place within the cycle time of package placement. This cycle time is desirably short, in order to provide a high throughput of packages. For example, a desirable system might have a cycle time of two seconds.
The complete determination of the position of an object on a stack, and, more specifically, the determination of the displacement of an object from a desired position, requires obtaining six offsets with respect to the desired position. These offsets include, in a three-axis coordinate system, three translation offsets due to the translation of the package along each axis, and three rotational offsets due to the rotations of the package about the three axes. Existing machine vision systems designed for inspection and sensing over the conveyor belt lack the capability of measuring six offsets from a single image. Systems, such as stereo sensing systems, have been provided which are capable of analyzing images made from different locations, but such systems require processing a large quantity of data. Processing a large quantity of data is either difficult or impossible to achieve in real time or, if possible, requires substantial expense in computational hardware.
In addition, existing machine vision systems are subject to difficulties in interpreting data as a result of uneven or unpredictable ambient lighting.
It is thus an object of the invention to provide a method and apparatus for determining the location and orientation of a rectangular object with respect to a reference location and orientation in a short period of time.
It is a further object of this invention to provide a method and apparatus for determining the location of a rectangular object with respect to a reference position that includes effective illumination of the object so that data is independent of ambient lighting conditions.
Additional objects and advantages of the present invention will become evident from the detailed description of a preferred embodiment which follows.

Method and apparatus for determining the displacement of a rectangular object with respect to a reference position


A stabilizing vane for use with an archery arrow includes an elongate vane body with an inclined surface attached thereto. The inclined surface is confined substantially within the upper portion of the vane body spaced from the arrow shaft so as to be cooperable with an arrow rest. The inclined surface can be oriented to optimize arrow rotation and centering.

1. Field
The invention is in the field of archery arrows and stabilizing vanes for archery arrows.
2. State of the Art
It is generally known that the flight of an archery arrow can be stabilized to some degree by causing the arrow to rotate during its flight. In the prior art, where arrow rotation is desired, the arrow vanes or fletching have been attached to an arrow shaft at an angle to the longitudinal axis of the shaft to impart rotation to the shaft during flight. However, with many of the newer arrow rests currently in use, the arrow supporting portion of the rest contacts the arrow shaft adjacent the vanes as the vanes pass through or over the rest. With such rests, angled vanes have difficulty clearing the arrow rest when the arrow is shot. The vanes often contact portions of the rest, thereby deflecting the arrow's path. Thus, rather than stabilizing the arrow's flight, the contacting of the vanes with the arrow rest actually destabilize and interfere with the accurate flight of the arrow. Thus, many arrows used today have vanes aligned with the longitudinal axis of the arrow shaft and there is no means provided for causing rotation of the arrow during flight. Other arrows have very limited vane angle so that the vanes will clear most arrow rests. However, the small degree of vane angle gives very limited arrow rotation so its stabilizing effect is very limited.


The present invention relates to a ball mill having a substantially horizontal axis of rotation and including a drum supported by two trunions having the same axis of rotation and situated at respective ends of the drum, raw coal being conveyed by substantially vertical pipework to the vicinity of a cylinder having the same axis of rotation and disposed within each trunion so as to open out into the drum, with the space lying between each trunion and its cylinder being connected to a pulverized coal outlet duct via a separator. A raw coal guide member is disposed beneath the pipework, conveying coal under gravity into the inside of the cylinder which includes a rigid Archimedes' screw on its inside surface, a main air feed being provided on said pipework upstream from the separator, all of said air being channeled towards the inside of the cylinder.

Within each trunion of such a mill that is known, there is disposed a hollow cylinder carrying a resilient Archimedes' screw on its outside surface for the purpose of feeding raw coal, and onto which the raw coal falls from the pipework so as to be conveyed into the drum. "Main" air is injected into the drum via the inside of the cylinder so as to entrain the grains as milled inside the drum. The space between the trunion and the screw serves to evacuate the pulverized coal and it is connected to a separator. Additional air is injected into the pipework upstream from the separator.
By way of example, one such mill is described in patent application FR 2 721 711.
That type of mill suffers from the following technical problems.
It turns out that small quantities of additional air are incapable of providing effective pre-drying of the coal, with air flow rate being low when the mill is operating at full load.
Raw coal dropping onto the blades of the resilient screw gives rise rapidly to major wear thereof. This wear is accelerated by the pulverized coal as mixed with air passing through said space between the trunion and the screw.
Thus, said space serves both to feed raw coal into the drum and also to extract pulverized coal for feeding to the separator. These two flows of matter in opposite directions generate turbulence and a flow that is disturbed, thereby giving rise to high headlosses and to poor distribution of air and of pulverized coal within the separator.


A wheel data detection system includes a wireless data detection device and a data receiver. The wireless data detection device includes: a body adapted to be mounted to an inner surface of a rim, and having a closed end, an open end disposed to be in spatial communication with a chamber of a wheel, and a cavity defined between the closed and open ends; a radio frequency unit for receiving and transmitting radio signals; a detector for detecting pressure in the cavity and for generating a pressure signal according to the pressure detected thereby; and a control unit for processing the pressure signal into a data output. The radio frequency unit converts the data output received from the control unit into the radio signal to be transmitted thereby. The data receiver receives the radio signals transmitted by the radio frequency unit.

1. Field of the Invention
The invention relates to a data detection system, more particularly to a wheel data detection system and a wireless data detection device thereof that are easily applied to wheels of a vehicle.
2. Description of the Related Art
An abnormal tire pressure not only shortens the service life of the tire and increases the fuel consumption of the vehicle, but also degrades the brake performance of the vehicle while increasing the risk of flat tires. When tire pressure increases, the braking distance traveled by the vehicle increases as well. Therefore, in order to ensure driving safety, tire pressure monitoring systems (TPMS) are increasingly being employed in vehicles. In particular, the United States National Highway Traffic Safety Administration (NHTSA) has requested that all vehicles sold in the United States beginning the year 2007 are to be equipped with tire pressure monitoring systems in order to effectively prevent traffic accidents caused by abnormal tire pressure in vehicles.
A tire pressure monitoring system normally includes several detection devices that are mounted respectively on the wheels of a vehicle for detecting tire pressure, and a receiver device for receiving the detected tire pressure from the detection devices and for notifying users of the same. Numerous techniques related to tire pressure monitoring systems are present today.
U.S. Pat. No. 7,009,579 discloses mounting of one or more radio frequency devices directly on the wheels. Each of the radio frequency devices includes a wireless component and an antenna connected to the wireless component for transmitting and receiving radio signals. In this way, the radio frequency devices can be used as detection devices for detecting information such as tire pressure.
Moreover, as radio frequency identification (RFID) technology advances, multiple techniques related to RFID have been introduced. As disclosed in U.S. Pat. No. 6,724,301, an RFID tag loaded with rim identification information can be provided on an outer surface of the rim that faces the tire, and another RFID tag loaded with tire identification information can be provided on an inner surface of the tire. The identification information can include name of manufacturer, product number, date of production/use, etc., in order to allow users or manufacturers to track the source of the rims and tires. Further, the RFID tags can further be facilitated to detect tire pressure. In addition, Taiwanese Patent No. 563,639 also discloses mounting a detection device at the outer surface of the rim.
However, U.S. Pat. No. 7,009,579 discloses mounting of the detection device directly on the surface of the wheel. Thus, if a vehicle is to use the detection device, all of its wheels need to be replaced with new ones that have the detection devices mounted thereto, resulting in a relatively high cost. In addition, when the wheels equipped with the detection devices wear out and need replacement, the detection devices are disposed along with the worn out wheels and cannot be reused. On the other hand, according to U.S. Pat. No. 6,724,301 and Taiwanese Patent No. 563,639, the detection device is mounted on the outer surface of the rim facing the tire. This way, the rim and the tire need to be dissembled before the detection devices can be mounted, resulting in inconvenience during application.


After forming a first insulating film of a silicon nitride film, a silicon nitrided oxide film or a silicon carbide film, a second insulating film of a silicon oxide film is formed on the first insulating film. In a chamber of a high density plasma etching system, the second insulating film is selectively etched by using a first etching gas including a fluorocarbon gas having a cyclic structure as a principal constituent, so as to form an upper hole in the second insulating film. Subsequently, in the same chamber, the first insulating film is selectively etched by using a second etching gas including an oxygen gas as a principal constituent, so as to form a lower hole continuous to the upper hole in the first insulating film.

The present invention relates to a method for fabricating a semiconductor device, and more particularly, it relates to a technique to form a hole in a multi-layer insulating film composed of a lower insulating film made from a silicon nitride film, a silicon nitrided oxide film or a silicon carbide film and an upper insulating film made from a silicon oxide film.
In accordance with a recently increased degree of integration of semiconductor integrated circuit devices, there are increasing demands for refinement of semiconductor devices included in semiconductor integrated circuit devices, and therefore, a hole formed in an insulating film is required to have a high aspect ratio.
For example, in accordance with increased refinement of a MOS field effect transistor included in a semiconductor integrated circuit device, a capacitor used in a DRAM is also required to be refined. Accordingly, a stacked memory device in which a memory cell is disposed on a word line has become a leading memory device.
Now, a general stacked memory device will be described with reference to FIG. 5.
As shown in FIG. 5, a word line (gate electrode) 11 of a polysilicon film is formed on a semiconductor substrate 10 of a silicon substrate in which impurity diffusion layers 10a and 10b working as the source and the drain are formed, and a first interlayer insulating film 12 is deposited so as to cover the word line 11. A first contact 13 of a polysilicon film with its lower end connected to one impurity diffusion layer 10a is buried in the first interlayer insulating film 12.
A first insulating film 14 of, for example, a silicon nitride film working as an etching stopper film is deposited on the first interlayer insulating film 12, and a capacitor including a storage electrode 15, a capacitor dielectric film 16 and a plate electrode 17 is provided on the first interlayer insulating film 12. A second interlayer insulating film 18 is deposited on the first insulating film 14 so as to cover the capacitor. The upper end of the first contact 13 is connected to the storage electrode 15.
A second contact 19 with its lower end connected to the other impurity diffusion layer 10b is buried in the first interlayer insulating film 12, the first insulating film 14 and the second interlayer insulating film 18. A bit line 20 is provided on the second interlayer insulating film 18 so as to be connected to the upper end of the second contact 19.
Next, a conventional method for fabricating a stacked memory cell will be described. Beforehand, etching systems used in the conventional method for fabricating a stacked memory cell will be described with reference to FIGS. 9A and 9B.
FIG. 9A shows a rough cross-sectional structure of an inductively coupled plasma (ICP) etching system, that is, a high density plasma etching system. A lower electrode (sample table) 31 is provided in a lower portion of a chamber 30, and a semiconductor substrate 32 to be etched is held on the lower electrode 31. An induction coil 33 is provided on the outer face of the chamber 30, and RF power of 2.0 MHz is applied to the induction coil 33 by a first RF power supply 34. Also, RF power of 1.8 MHz is applied to the lower electrode 31 by a second RF power supply 35.
FIG. 9B shows a rough cross-sectional structure of a diode parallel plate RIE system, that is, a low density plasma etching system. A lower electrode (sample table) 41 is provided in a lower portion of a chamber 40, and a semiconductor substrate 42 to be etched is held on the lower electrode 41. RF power of 13.5 MHz is applied to the lower electrode 41 by an RF power supply 43. Also, an upper electrode 44 is provided in an upper portion of the chamber 40, and the upper electrode 44 is grounded.
Now, the conventional method for fabricating a memory cell by using the two kinds of etching systems of FIGS. 9A and 9B will be described with reference to FIGS. 6A through 6D, 7A through 7D and 8A through 8D.
First, as shown in FIG. 6A, after forming a word line 11 on a semiconductor substrate 10, a first interlayer insulating film 12 is deposited on the semiconductor substrate 10 so as to cover the word line 11. Thereafter, a first contact 13 of a polysilicon film is buried in the first interlayer insulating film 12 so as to be connected to one impurity diffusion layer 10a at its lower end.
Next, a first insulating film 14 of, for example, a silicon nitride film working as an etching stopper film and a second insulating film 21 of, for example, a silicon oxide film are successively deposited on the first interlayer insulating film 12.
Then, as shown in FIG. 6B, after an anti-reflection film 22 of an organic film is formed on the second insulating film 21, a first resist pattern 23 having a hole opening 23a is formed on the anti-reflection film 22.
Subsequently, by using the inductively coupled plasma etching system of FIG. 9A, the anti-reflection film 22 and the second insulating film 21 are successively etched with the first resist pattern 23 used as a mask, so as to form an upper hole 24a in the second insulating film 21 as shown in FIG. 6C.
The etching conditions for this etching are as follows: The pressure within the chamber 30 is set to 1.33 Pa; RF power (coil power) of 2700 W is applied to the induction coil 33 by the first RF power supply 34; and RF power (bias power) of 1300 W is applied to the lower electrode 31 by the second RF power supply 35.
In the etching of the anti-reflection film 22, a first etching gas of a mixture of a C2F6 gas (with a flow rate of 40 ml/min. (standard condition)) and an O2 gas (with a flow rate of 5 ml/min. (standard condition)) is introduced into the chamber 30. In the etching of the second insulating film 21, a second etching gas of a mixture of a C2F6 gas (with a flow rate of 40 ml/min. (standard condition)) and an O2 gas (with a flow rate of 2 ml/min. (standard condition)) is introduced into the chamber 30. Thus, the anti-reflection film 22 and the second insulating film 21 can be successively etched, and the etching can be definitely ended on the top face of the first insulating film 14.
Next, as shown in FIG. 6D, the resist pattern 23 and the anti-reflection film 22 are removed by ashing using oxygen plasma, and the resultant substrate is cleaned.
Thereafter, by using the diode parallel plate RIE system of FIG. 9B, the first insulating film 14 is etched by using, as a mask, the second insulating film 21 in which the upper hole 24a has been formed (namely, the patterned second insulating film) as shown in FIG. 7A, so as to form a lower hole 24b in the first insulating film 14. Then, etching residues are removed by the ashing. Thus, a hole 24 composed of the upper hole 24a and the lower hole 24b is formed.
The etching conditions for the etching of the first insulating film 14 are as follows: The pressure within the chamber 40 is set to 5 Pa; RF power of 600 W is applied to the lower electrode 41 by the RF power supply 43; and a third etching gas of a mixture of a CHF3 gas (with a flow rate of 110 ml/min. (standard condition)) and an O2 gas (with a flow rate of 12 ml/min. (standard condition)) is introduced into the chamber 40.
Also, the conditions for the ashing are as follows: The pressure within the chamber 40 is set to 133 Pa; RF power of 100 W is applied to the lower electrode 41 by the RF power supply 43; and a fourth etching gas of a mixture of a CF4 gas (with a flow rate of 100 ml/min. (standard condition)) and an O2 gas (with a flow rate of 100 ml/min. (standard condition)) is introduced into the chamber 40.
Next, as shown in FIG. 7B, a first polysilicon film 15A doped with, for example, phosphorus is deposited on the top face of the second insulating film 21 and on the wall and the bottom of the hole 24. Thereafter, a second resist pattern 24 is formed on the first polysilicon film 15A as shown in FIG. 7C.
Then, as shown in FIG. 7D, the second resist pattern 24 is etched back, so that a storage electrode forming region (corresponding to a portion present within the hole 24) of the second resist pattern 24 can remain. In other words, a portion of the first polysilicon film 15A present on the second insulating film 21 is exposed. This procedure is performed in order to protect a portion of the first polysilicon film 15A to be formed into a storage electrode in subsequently performed etching of the first polysilicon film 15A.
Next, as shown in FIG. 8A, the first polysilicon film 15A is etched by using the second resist pattern 24 as a mask, so as to form a storage electrode 15 in a bottomed cylindrical shape (with a U-shaped cross-section) from the first polysilicon film 15A. Thereafter, the second insulating film 21 and the second resist pattern 24 are removed by a vapor HF treatment, so as to expose the storage electrode 15 as shown in FIG. 8B.
Then, as shown in FIG. 8C, for example, a silicon nitrided oxide film 16A and a second polysilicon film 17A doped with, for example, phosphorus are successively deposited over the storage electrode 15 and the first insulating film 14. Thereafter, the second polysilicon film 17A, the silicon nitrided oxide film 16A and the first insulating film 14 are patterned, thereby forming a plate electrode 17 from the second polysilicon film 17A and a capacitor dielectric film 16 from the silicon nitrided oxide film 16A as shown in FIG. 8D.
Subsequently, although not shown in the drawings, a second interlayer insulating film 18, a second contact 19 and a bit line 20 are formed, resulting in completing the semiconductor device of FIG. 5.
In the aforementioned stacked memory device, the capacitance of the capacitor is determined depending upon the area of a portion where the storage electrode 15 opposes the plate electrode 17, namely, the height of the storage electrode 15. The height of the storage electrode 15 depends upon the depth of the hole 24. Accordingly, in order to attain constant capacitance of the capacitor, it is very significant to control the depth of the hole 24 to be constant.
Therefore, the first insulating film 14 working as an etching stopper film in the etching of the second insulating film 21 is formed below the second insulating film 21. However, since the first insulating film 14 is present below the second insulating film 21, it is necessary, for forming the hole 24, to etch the first insulating film 14 in addition to the second insulating film 21.
In the etching of the second insulating film 21, the second etching gas of a mixture of a C2F6 gas and an O2 gas is introduced into the chamber 30 of the inductively coupled plasma etching system, so as to generate high density plasma to be used for the etching.
In the etching of the first insulating film 14, the third etching gas of a mixture of a CHF3 gas and an O2 gas is introduced into the chamber 40 of the diode parallel plate RIE system, so as to generate low density plasma to be used for the etching.
The reasons why the different etching systems are thus used in the etching of the second insulating film 21 and in the etching of the first insulating film 14 will now be described.
The first reason is as follows: Since the second insulating film 21 has a comparatively large thickness, the etching time is too long if it is etched by using low density plasma. Accordingly, the second insulating film 21 is etched preferably by using high density plasma. In contrast, the first insulating film 14 has a comparatively small thickness. Therefore, if it is etched by using high density plasma, the etching rate is varied in the substrate plane, and hence, the depth of the hole 24 is varied and the etching end point is difficult to detect. Accordingly, the first insulating film 14 is etched preferably by using low density plasma.
The second reason is as follows: Since the second insulating film 21 is made from a silicon oxide film, it is necessary to use the etching gas of a mixture of a C2F6 gas and an O2 gas in the etching of the second insulating film 21. On the other hand, since the first insulating film 14 is made from a silicon nitride film, it is necessary to use the etching gas of a mixture of a CHF3 gas and an O2 gas in the etching of the first insulating film 14. Thus, it is necessary to change the etching gas between the etching of the second insulating film 21 and the etching of the first insulating film 14.
For these reasons, the different etching systems are used in the etching of the second insulating film 21 and the etching of the first insulating film 14. However, the use of the different etching systems increases the number of procedures and also largely increases the time required for forming a hole (turn around time; TAT).
Also in the case where the first insulating film 14 is made from a silicon nitrided oxide film or a silicon carbide film instead of a silicon nitride film, the same problems arise.

Method for fabricating semiconductor device comprising forming holes in a multi-layer insulating film

Matsushita Electric Industrial Co., Ltd.


A method and an apparatus for retrieving a form template including one or more rendering attributes for rendering one or more partitions of a form are described. Whether the partitions of the form can be rendered in compliance with style constraints is determined according to the rendering attributes. An updated form template is generated such that at least one of the rendering attributes is updated. Partitions of the form can be rendered based on the updated template in compliance with the style constraints.

When designing electronic forms (or a form to be filled out on a computer) for similar business functions, it is a common practice to use templates for simplifying the design process. However, many electronic programs for form design either do not support templates for forms or rely on complicated yet limited template configuration mechanisms. For example, a form configuration tool based on XLST (Extensible Stylesheet Language Transformations) may require a designer to express form adaptation in XLST language. However, such a complicated process defies the purpose of form design by adapting an existing form.
Besides, many design platforms are not optimized to use an existing form as a template for generating other forms. Even if it is possible to adapt a form template in these design platforms, the adaptation process may be costly in both human and computing resources. As a result, the design cycle based on form adaptation may be prolonged and the approach becomes practically undesirable.
In addition, adapting or changing a template to derive new form designs may be subject to many design constraints or requirements, for example, design guidelines or styles depending on specific business needs. Often times, it is labor intensive and error prone to manually enforce such constraints or requirements when adapting a form. Therefore, existing methods for form adaptation may be inefficient, ineffective or even frustrating to use.

Method and apparatus for form adaptation


A medical system includes a medical device and a display for displaying a plurality of visual elements. The plurality of visual elements are associated with functions of the medical device. The medical system also includes a plurality of visual profiles for facilitating in controlling visual appearance of the plurality of visual elements displayed on the display, and a visual profile selector for selecting at least one of the plurality of visual profiles based on a state of the medical device.

A display screen on a medical device allows for a clinician to visibly see some parameters of the medical device. However, adjustments of the display screen typically does not allow for optimal viewability. In particular, current medical devices do not allow for color customization to inform the user of how the medical device operates.
The drawings referred to in this description should be understood as not being drawn to scale except if specifically noted.

Displaying visual elements on a medical device


A method and system to generate a CLI command designed to output a configuration dump of a networked device is described. The method and system allows generation of a command that discovers the state value parameters of the device, and from those discovered state value parameters constructs a CLI command script that, when executed, sets the networked device back to the configuration existing when the command was initially executed. The method and system provides templates and routines that may be customized by the user to form a command specific to the networked device.

Modern computer networks resemble a web of communication lines that meet at a plurality of node points, such that any one node point may be reached from another node point along many different paths. Different types of devices are connected to the network at the nodes, to perform functions associated with network traffic or simply to send and receive data from the network. Some of the devices are routers, which forward network traffic along optimized paths. Other devices may include any type of network enabled device, which is able to communicate with other networked devices by exchanging data over the network.
Routers manufactured by the Cisco Systems Corporation are widely used. Cisco routers are managed by a Command Line Interface (CLI), which is a collection of text commands that are typically entered by the user at a command prompt, using a computer terminal. In general, routers are formed by powerful microprocessors, memory units and command consoles which allow a user to configure the manner in which the router directs the flow of network traffic according to the computed optimal paths. Other devices connected to the network may be configured so that they are capable of interacting with routers, and are often designed with CLI command sets that are compatible with the Cisco Internetworks operating system. In particular, applications used to remotely manage these devices, as well as the routers themselves, may be designed to be compatible with the Cisco CLI command set, to provide familiar commands and software organization to developers used to work with Cisco systems.
On occasions, the operation of the networked devices is disrupted by an abnormal condition, an unexpected event or other abnormality, and the networked device stops functioning normally. This abnormal condition, generally called a "crash", often requires a restart of the networked device in order to be resolved. The user may also attempt to improve the performance of the device by changing configurations, in which case each successive configuration can be referred to as a "candidate version" of the final desired configuration. It is often valuable to return the device to a known valid configuration, either in response to the conditions of the network that led to the failure, or to back out of a "candidate version" configuration known to be flawed.
The CLI commands used to set a device to one of these various configurations are typically placed into a script file, due to the complexity and volume of commands required to fully set a device's configuration. It is useful thus to generate a script file for an existing configuration of the device, so that the device can later be returned to that configuration. Generating such a script file typically is a complex and time consuming process, which needs to be repeated every time changes are made to the device's features or to the CLI command set.

CLI configuration dump command support generation


A system and method are provided to hold a dialog between communicators while the communicators are viewing their images each other and which prevents the presence of an image display screen from being noticeable in a non-communication state. A first unit for the communicator generates and transmits first data indicating the image of the communicator. A second unit for the communication partner expands the first data received via a communication line to display the image of the communicator on the display screen, and generates and transmits second data indicating the image of the communication partner in front of the display screen. A human sensor is configured to detect that the communication partner is at a predetermined position in a home. Only during the period of the human sensor detecting that the communication partner is at the predetermined position, the display-cum-mirror forms a display screen, and otherwise, a mirror.

A communication technique for holding a dialogue between communicators in remote locations has been already known, and examples of such a technique include video chatting and videotelephony. In recent years, the technique for realizing a dialogue with a higher realistic sensation has been developed (see, e.g., Japanese Patent Document Nos. 2011-113206 A ("the '206 Document") and 2009-60220 A ("the '220 Document").
The '206 Document describes the technique on video communication made while communicators are viewing their images each other. Such a technique uses a display to resemble a single window, and an image of the space, where a communication partner is present, as viewed from a communicator can be displayed on the display according to the point of view of the communicator as if the communicator was, through the window, viewing the space where the communication partner is present (i.e., motion parallax). This allows image display with a depth.
The '220 Document describes a communication system realizing communication between different spots via a network. In such a system, the positions of communicators in communication between different spots are determined. Based on determination results, at least any of the operation of changing microphone sensitivity to sound at the above-described positions or the operation of increasing sound output from a speaker at the above-described positions is performed. Accordingly, voice of the communicators having a dialogue between the different sports can be easily captured.


A nutritional supplement contains plural parts. Each of the plural parts is chronologically appropriate for its scheduled time of consumption. The nutritional supplement is contained in a palatable base, for example, a food bar which masks any unpleasant taste or texture of the nutrient. The nutritional supplement may contain any one or several nutrients including drugs, vitamins, herbs, hormones, enzymes and/or other nutrients in chronologically appropriate dosages in each part or sub-part.

Many drugs, vitamins, herbs, hormones, minerals, enzymes and other nutrients (hereinafter generally referred to as nutrients) have a very short half life in the body. A limited half life is advantageous for many nutrients because of the constantly changing conditions within a biological organism. For example, many hormones exhibit a diurnal cycle either resulting from changing metabolic activities and needs as an organism progresses through a daily cycle. For other nutrients, cycling levels are unwanted, for example, for vitamin C, a uniformly high titer is often desired.
Vitamin C is one example of a short half life nutrient. The half life of vitamin C is approximately 2 to 3 hours. Multiple dosages spaced throughout the day are essential to maintaining a desired uniformly high level of vitamin C in the body.
For other nutrients, maintaining a uniform level in a body or a tissue of an organism throughout the day is unnecessary or undesirable. For example, metabolic enhancers tend to be most effective when administered in the morning whereas other nutrients, for example, growth hormone enhancers, tend to be most effective when administered at night or before a sleep period.
Still other nutrients may require large dosages in order to be effective. For example, in order to be effective as systemic antioxidants, some vitamins would require consumption of approximately 40 tablets per day. Because of the bulk of the nutrient and/or absorptive capacity of the organism, it may be advantageous to disperse consumption of these nutrients into several doses throughout the day.
Additionally, some athletes may, as part of a multi-day training regimen, overlay a multi-day nutrient needs cycle on top of their diurnal cycle. Athletes or other competitors may also have specific chronologically determined needs, for example, an athlete may want to peak or maximize a performance during a particular scheduled event. Similarly, travelers traversing several time zones often find they must overcome their inherent diurnal cycle. A nutrient supplement satisfying their inherent or home cycle or preferably a nutrient supplement accommodating to a new cycle or helping to accommodate to a new cycle would be advantageous.
Therefore, there are several different needs for scheduling nutrient supplementation throughout the day. For some nutrients, maintenance of a uniform dosage throughout the day requires multiple scheduled administrations of nutrients throughout the day. For other nutrients, where a uniform systemic level may not be desired, scheduling timely administration of nutrients may be important. For still other supplements the physical bulk or absorptive limitations may require chronologically dispersed administrations of nutrients throughout the day. Additionally, when an individual may desire to overcome their diurnal cycle, may desire to alter their diurnal cycle or may desire to select a peak timing of their performance, a simple means for administering multiple scheduled nutritive supplements is desired.


Methods and apparatus that may help reduce standby current in memory devices are provided. By separating equalizing and precharging functions into separate circuit structures, current paths between a source of precharge voltage and a defective wordline (e.g., having an inadvertent short to a bitline due to a manufacturing defect) may be eliminated.

1. Field of the Invention
The invention generally relates to memory devices, and more particularly to reducing current consumption of memory devices.
2. Description of the Related Art
Users of electronic devices often desire large amounts of memory in a small package. Where the electronic devices are portable (e.g., battery powered), users may also desire electronic devices which do not consume as much power and therefore have a longer battery life. Thus, manufacturers of electronic devices typically desire small, high density memory devices with low power consumption. Of particular importance is the amount of current consumed when the memory devices are in a standby mode (i.e., standby current), which typically has a specified maximum value. To meet the demand for small, high density memory devices, memory manufacturers have created dynamic random access memory (DRAM) devices with the smallest available features (e.g., transistors and control lines) and with densely packed memory cells. Examples of DRAM devices include single data rate (SDR) and double data rate (DDR) DRAM devices, pseudo static random access memory (PSRAM) devices, and the like, all collectively referred to herein as DRAM devices.
However, as the size of features in a memory chip shrinks and as the memory density of a memory chip increases, small, uncontrollable errors in the manufacturing process may cause defects at a high cost to the manufacturer. An example of a possible defect is a short (e.g., an unintended electrical connection) between a wordline and a bitline used to access a memory cell. In some bitline structures, these shorts may result in increased standby current due to voltage differences created between the wordline and bitline when the bitline is maintained at a precharge voltage level.
For example, FIG. 1 illustrates an exemplary DRAM bitline structure 100 in which equalization circuitry 110 maintains complementary bitline pairs 102 at a precharge voltage level (VBLEQ) when wordlines 104 are not activated to access corresponding memory cells 101. In the "folded" bit line structure shown, left and right side bit line pairs (102L and 102R) share a common set of bit line sense amplifier (BLSA) 120. I/O gate 130 drives the output of the sense amplifier out of the array (e.g., to a secondary sense amplifier) in conjunction with a column select line (CSL) signal.
Switches (or switches) 140L and 140R are provided to select whether the left or right side bit line pairs are coupled to the BLSA 120, to access memory cells 101 in the left or ride side of the array, respectively. In other words, when accessing memory cells 101R on the right side, switch 140R may be turned on to couple complementary bit line pair 102R to BLSA 120, while switch 140L may be turned off to isolate complementary bit line pair 102L to BLSA 120. Similarly, when accessing memory cells 101R on the left side, multiplexor (or switch) 140L may be turned on while switch 140R may be turned off.
For some embodiments, separate equalization circuits 110 (provided outside the switches 140) may be provided for each complementary bit line pair 102L and 102R. However, a single equalization circuitry 110 located between the switches 140, as shown, may be shared between both complementary bit line pairs and provide a more compact design.
FIG. 2 illustrates an exemplary precharge and equalization circuit 110, controlled by an equalization signal (EQ). As illustrated, the circuit 110 may include a separate equalization circuit (MEQ) 112 which illustratively includes an N-type transistor for coupling both bit lines of a complimentary bit lines 102 together in response to the EQ signal, thereby causing the bit lines to reach a common voltage level (i.e., equalize). A separate precharge circuit (MBLEQ) 114 illustratively includes a pair of N-type transistors to apply a precharge voltage signal (VLBEQ) to both bit lines in response to the EQ signal.
The timing diagram shown in FIG. 3 illustrates how the equalization circuit 110 operates to equalize and precharge complementary bit line pairs before and after a row access. As illustrated, prior to the row access (time T5), both switches are turned on (MUX_L and MUX_R=HI) and EQ is asserted, thereby allowing bit line pairs on both sides to be equalized and precharged (to VBLEQ). The access begins at T1, for example, with a Row_Active signal being asserted, which causes the switch 140 for the side not being accessed to be turned off (illustratively, a left side access is performed) and the EQ signal to be de-asserted, thereby decoupling the bit lines. At time T2, the selected word line (e.g., one the left side) is activated and sensing of corresponding memory cells occurs in period T3.
In period T4, the selected wordline is de-activated, the switch 140 for the non-selected side is again turned on, and the EQ signal is again asserted. To ensure none of the corresponding memory cells are coupled to the bit lines, a zero voltage or negative voltage is typically applied to de-activated wordlines, resulting in a voltage difference between the wordlines and bitlines. Asserting the EQ signal and turning on both switches 140 ensures the bit lines are equalized and maintained (in period T5) at the VBLEQ by equalization circuit 110 until the next access.
Unfortunately, this approach results in increased current draw in the event a defect causes a short 402 between a (defective) wordline 104D and a bitline 102, as shown in FIG. 4. Even thought the defective wordline would likely be replaced by redundancy, due to the difference in voltage between the defective wordline 104D (maintained at 0V or less) and the bitline 102 (maintained at VBLEQ), current (ISHORT) may flow from the equalization circuit 110 to the defective wordline across the short. Compounding the problem, in case the defective wordline 104D is maintained at a negative voltage (below 0V), a charge pump, which has inherent inefficiencies, is typically utilized. For example, assuming 50% efficiency, the charge pump has to consume twice as much current to generate ISHORT.
As previously described, standby current consumption is particularly important for low powered memory devices. In some cases, increased current consumption due to bitline shorts may result in a memory device exceeding the specified minimum standby current, thereby resulting in decreased production yield. Accordingly, what is needed are methods and apparatuses for reducing standby current consumption of a memory device due to bitline shorts.

Technique to suppress bitline leakage current


A new Solenostemon plant named ‘Mos Burvet’ particularly distinguished by the yellow-green and medium greyed-purple colored foliage, with an upright, well branched and uniform plant habit.

The present invention comprises a new Solenostemon, botanically known as Solenostemon scutellarioides, and hereinafter referred to by the variety name 'Mos Burvet'.
'Mos Burvet' is a product of a planned breeding program. The new cultivar has yellow-green and medium greyed-purple colored foliage, with an upright, well branched and uniform plant habit.
'Mos Burvet' originated from a hybridization made in January 2006 in a controlled breeding environment in Andijk, Netherlands. The female parent was the unpatented, proprietary plant designated 'CS06-16-1' with smaller and fewer leaves, less branching and thinner stems.
The male parent of 'Mos Burvet' was the unpatented, proprietary plant designated 'CS06-1-1' with smaller leaves, and thinner stems. The resultant seed was sown in July 2006.
'Mos Burvet' was selected as one plant within the progeny of the stated cross in September 2006 in a controlled environment in Andijk, Netherlands.
The first act of asexual reproduction of 'Mos Burvet' was accomplished when vegetative cuttings were propagated from the initial selection in September 2006 in a controlled environment in Andijk, Netherlands.


Methods, devices, and systems are provided for the delivery of agents (e.g., nucleic acids, proteins, organic molecules, organelles, antibodies or other ligands, 5 etc.) into live cells and/or the extraction of the same from said cells. In various embodiments the photothermal platforms and systems incorporating such photothermal platforms are provided that permit efficient, high-throughput cargo delivery into live cells.

Transferring cargo into mammalian cells over a wide range of sizes, including proteins, DNA, RNA, chromosomes, nuclei, and inanimate particles, such as quantum dots, surface-enhanced Raman scattering (SERS) particles, and microbeads, is highly desirable in many fields of biology. Delivery methods, such as endocytosis, can entrap cargo in an endosome, where the low pH microenvironment and lytic enzymes often lead to cargo degradation (Luo and Saltzman (2000) Nat. Biotechnol. 18: 33-37). Viral and chemical delivery methods package the cargo inside a virus or form chemical complexes that enhance uptake (Naldini et al. (1996) Science, 272: 263-267; Feigner et al. (1987) Proc. Natl. Acad. Sci. USA, 84: 7413-7417). However, toxicity, cell-type specific uptake, and more importantly limited cargo packing capacity impose a significant constraint on cargo size and transferable cell types (Luo and Saltzman, supra.).
Physical transfer methods include electroporation (Chu, et al. (1987) Nucleic Acids Res. 15: 1311-1326) and sonoporation (Mitragotri (2005) Nat. Rev. Drug Discovery, 4: 255-260), which are methods that produce randomly distributed nanoscale pores, and optoporation (Tirlapur and Konig (2002) Nature, 418: 290-291; Vogel, et al. (2005) Appl. Phys. B: Laser Opt., 81: 1015-1047; Clark et al. (2006) J. Biomed. Opt., 11: 014034), which is a method that generates pores on the cell membrane at the laser focal point. Small cargos are delivered through these pores into cells by thermal diffusion or by an electric field. Delivery of large cargo with these methods, however, has low efficiency due to the slow speed of cargo diffusion and decreasing cell viability with increasing pore size (Stevenson et al. (2006) Opt. Express, 14: 7125-7133).
Microcapillary injection uses a sharp glass tip to mechanically penetrate a cell membrane for delivery (see, e.g., King (2004) Meth. Mo. Biol., 245: Gene Delivery to Mammalian Cells 1; Humana Press Inc. Totowa, N.J.). However, mechanical trauma from membrane penetration limits the typical pipet tip to about 0.5 um in diameter in order to maintain cell viability (see, e.g., Han et al. (2998) J. Nanomed. Nanotechnol. Biol. Med., 4: 215-225).
Cargos larger than the pipet tip cannot be injected due to pipet clogging and cargo shearing. Electro-injection, a method that combines electroporation with microcapillary injection, has demonstrated delivery of small molecules such as RNA and plasmid DNA, into live cells (see, e.g., Boudes et al. (208) J. Neurosci. Meth., 170: 204-211; Kitamura et al. (2008) Nat. Meth., 5: 61-67, and the like) and bacteria delivery into artificial lipid vesicles (see, e.g., Hurtig and Orwar (2008) Soft Matter, 4: 1515-1520). Electro-injection works by weakening the cell membrane with an electric field, followed by gentle mechanical penetration into the cell.
Simple lipid assisted microinjection (SLAM) techniques (Laffafian and Hallett (1998) Biophys. J., 75: 2558-2563) incorporate synthetic lipid molecules at the tip of a glass microcapillary. Contact of the SLAM micropipette with a cell membrane allows the lipid molecules to fuse with the cell membrane to form a continuous and temporary pathway for cargo delivery. This method avoids problematic zigzag stabbing motions of the micropipette tip through the cell membrane. However, the lipohilic interactions with cargo and cell membrane can produce unwanted biological effects in the cell as well as with the delivery cargo, limiting this method to specific cell types and cargo contents.

High-throughput cargo delivery into live cells using photothermal platforms

The Regents of the University of California


The present invention relates to a method of fabricating an improved lithium silicate glass ceramic and to that material for the manufacture of blocks for dental appliances using a CAD/CAM process and hot pressing system. The lithium silicate material has a chemical composition that is different from those reported in the prior art with 1 to 10% of germanium dioxide in final composition. The softening points are close to the crystallization final temperature of 800° C. indicating that the samples will support the temperature process without shape deformation.

There are many products available that employ lithium disilicate glass ceramic covered by several U.S. patents. Some of these patents claim a process for the preparation of shaped translucent lithium disilicate glass ceramic products from a mixture of basic components (SiO2, Al2O3, K2O, Li2O, plus pigments and fluorescent oxides). The thermodynamic solid-liquid equilibrium of the system consisting of lithium oxide (Li2O) and silicon dioxide (SiO2) has been extensively studied even before that material was used as a dental ceramic (1-3, 5-6).
For those skilled in the art this experimental solid-liquid equilibrium can explain with an extraordinary simplicity how different glass ceramics can be obtained using the same two components when they are combined in different proportions. The same solid-liquid equilibrium shows what type of stable crystal is produced as a final product of crystallization when a specific mix composition of the two components are blended, melted, and crystallized to achieve the final product.
The crystallographic data for intermediate crystal compounds in the Li2O—SiO2 system is given by the Landolt-Bornstein tables. The following are the types of crystal compositions possible in the Li2O—SiO2 system: Li8SiO6, Li4SiO4 or lithium ortho silicate monoclinic and orthorhombic; Li6Si2O7, Li2SiO3 or lithium silicate; Li2Si2O5 or lithium disilicate monoclinic and orthorhombic; and Li2Si3O7 lithium trisilicate.
Thus when the silicon dioxide to lithium oxide molar ratio (SiO2/Li2O) is greater than or equal to two, meaning two moles of SiO2 are mixed with one mol of Li2O, the crystallized glass ceramic product will be mainly lithium disilicate (SiO2/Li2O). This molar ratio of two is equivalent to a molar composition of lithium oxide in the mixture of 33% (67% as SiO2). When the same molar relationship is below 2.0, (e.g. 1.7) only lithium silicate crystals are produced (Li2O.SiO2). The lithium oxide molar composition for a ratio of 1.7 is equivalent to 37% molar (63% SiO2). The type of resulting crystal due to the specific composition ratios gives to the glass ceramic its own distinguishable chemical and physical properties. Surprisingly, the same behavior is obtained if these two main components (silicon dioxide and lithium oxide) maintain their molar ratio below two even if they are mixed with other oxides as additives and modifiers. The other common oxides mixed are aluminum oxide, potassium oxide, calcium oxide, zirconium oxide and coloring oxides that are incorporated into the glass matrix and give the glass ceramic its final color and translucency.
Due to the final composition of this invention using a molar ratio of SiO2/Li2O between 1.7 to 1.9, the only phase present is lithium silicate, instead of lithium disilicate, as a main constituent of the glass ceramic as a final product. For instance, a glass ceramic with a molar ratio of silicon dioxide to lithium oxide greater than or equal to two plus additional oxides will produce, after full crystallization a lithium disilicate glass ceramic with a melting temperature of 920° C. and a linear thermal coefficient of expansion of 10.5×10−6/° C. as a final product and composition. In addition, during the production of this type of glass ceramic the cast material is subjected to at least three different heat treatments: an annealing cycle for eliminating accumulated stresses, a nucleation cycle for the formation of lithium metasilicate or unstable lithium silicate, and finally a third thermal cycle to convert the unstable lithium silicate or metasilicate into a stable lithium disilicate. This is clearly shown in the following US patents:
Examples of those types of glass ceramics are claimed in Barret et al in U.S. Pat. No. 4,189,325 which discloses a lithium silicate glass ceramic where the raw materials are blended, melted at 1315° C. and held for 24 hours for homogenization, fritted and crushed, melted again and cast into preheated molds. They disclose a composition of silicon dioxide to lithium oxide molar ratio of two, producing a dental ceramic composed of lithium disilicate.
U.S. Pat. No. 4,480,044 to McAlinn discloses a glass ceramic formulation where the lithium silicate glass ceramic in their intermediate process stage has a thermal expansion of 13×10−6/° C. and the lithium disilicate has a thermal expansion of 11.4×10−6/° C. They disclose a machinable lithium disilicate glass ceramic with a percentage of silicon dioxide of 79.8%.
U.S. Pat. No. 4,515,634 to Wu et al discloses a castable glass ceramic composition useful as a dental restorative material. The components are blended and melted at 1400 to 1450° C., then quenched in water, dried, milled to a powder, and melted again at 1400° C. for 4 hours. Then the melt is cast into copper molds and transferred to the annealing process. The castable glass ceramic of the invention is lithium disilicate with a silicon dioxide to lithium oxide molar ratio of two, equivalent to silicon dioxide weight composition of 65%-74.7% and lithium oxide weight composition of 14.8-16.4%.
U.S. Pat. No. 5,219,799 to Beall et al discloses a lithium disilicate glass ceramic with silicon dioxide weight composition of 65%-80% and lithium oxide compositions of 8.0-19.0%. The blended raw materials are melted at 1450° C. for 16 hours and then poured into steel molds and annealed at 450° C.
U.S. Pat. No. 5,744,208 to Beall et al describes a lithium disilicate glass ceramic with silicon dioxide weight composition of 75%-95% and lithium oxide weight composition 3-15%. The raw materials are blended, and then melted in the range of 1450-1600° C. for about 6-10 hours. The glass is then poured into steel molds. The glass is then annealed, nucleated and crystallized to produce lithium disilicate glass ceramic in the range of 500° C. to 850° C.
U.S. Pat. No. 5,968,856 to Scheweiger et al discloses a lithium disilicate glass ceramic with compositions of silicon dioxide weight between 57%-80% and lithium oxide composition 11-19%. The components are blended and melted at 1500° C. for one hour and then quenched, dried, milled, dry pressed and sintered to form blanks. The composition requires the addition of lanthanum oxide to improve the flow properties, control the crystal growth and eliminate the strong reaction of the material with the investment material used.
U.S. Pat. No. 6,514,893 to Scheweiger et al discloses a lithium disilicate glass ceramic with silicon dioxide composition of 57%-75% weight and lithium oxide composition 13-19% weight and also containing lanthanum oxide. The components are blended and fused into granulates and comminuted to a powder. Coloring oxides are then added, and the ceramic is pressed and heat treated.
U.S. Pat. No. 6,455,451 to Brodkin et al discloses a lithium disilicate glass ceramic with silicon dioxide composition of 62%-85% weight and lithium oxide composition 8-19% weight. They disclose a method of making the lithium disilicate by melting the components at 1200 to 1600° C., followed by a quench, drying, and a heat treatment to form the glass ceramic, followed by comminuting to a powder, compacting and sintering to a blank and pressing to form the restoration.
U.S. Pat. No. 6,517,623 to Brodkin et al discloses a lithium disilicate glass ceramic pressable where the components are melted in the range of 1200 to 1600° C., quenched, heat treated, comminuting the glass ceramic to a powder, and then compacting the powder to a starting blank before sintering the blank or the restoration.
U.S. Pat. No. 6,606,884 to Scheweiger et al describes a lithium disilicate glass ceramic where the components are mixed and melted at 1200 to 1650° C., followed by pouring the glass into water, milling and compacting, and placing the blank in a heat treatment to sinter.
U.S. Pat. No. 6,802,894 to Brodkin et al shows a lithium disilicate glass ceramic with a silicon dioxide weight composition of 62%-85% and lithium oxide weight composition 8-19%. The components are mixed, melted at 1200 to 1600° C., and cast. The resulting glass is annealed at a range of 300 to 600° C., followed by subjecting the glass to a heat treatment from 400 to 1100° C.
U.S. Pat. No. 6,818,573 to Petticrew discloses a lithium disilicate glass ceramic with a silicon dioxide composition of 60%-80% weight and lithium oxide composition of 8-17% weight. The components are blended, melted, quenched, heat treated, milled to a powder, dry pressed, and hot pressed into the desired restoration.
U.S. Pat. No. 7,316,740 to Scheweiger et al claims a lithium silicate glass ceramic with silicon dioxide weight compositions of 64 to 73% and lithium oxide weight compositions of 13 to 17%. The lithium disilicate final product is demonstrated by means of a XRD pattern (FIG. 6) and DSC phase transformation curve from lithium metasilicate to lithium disilicate (FIG. 2). The DSC diagram shows the change in energy from the stage of metasilicate to disilicate, which is only necessary if lithium disilicate is desired to be the crystal phase used as a final product.
U.S. Pat. No. 7,452,836 to Apel et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as a final product. They also describe a glass ceramic with a molar ratio of silicon dioxide to lithium oxide of at least 2.3.
U.S. Pat. No. 7,867,930 to Apel et al shows a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as a final product.
U.S. Pat. No. 7,871,948 to Apel et al describes a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight, producing lithium disilicate as a final product. The glass of the starting material is subjected to an initial heat treatment form lithium metasilicate or unstable lithium silicate and then goes through a second heat treatment to convert the lithium metasilicate to a lithium disilicate.
U.S. Pat. No. 7,867,931 to Apel et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 64%-75% weight and lithium oxide composition of 13-17% weight producing lithium disilicate as the final product. They also describe a glass ceramic with a molar ratio of silicon dioxide to lithium oxide in the range of 2.3 to 2.5.
U.S. Pat. No. 8,042,358 to Schweiger et al discloses a lithium silicate glass ceramic with silicon dioxide composition of 65%-70% weight and lithium oxide composition of 14-16% weight producing lithium disilicate as the final product. In their specific process the raw materials such as carbonates, oxides and phosphates are prepared and melted in the range of 1300-1600° C. for 2 to 10 hours. They explain that in order to obtain a particularly high degree of homogeneity the glass melt obtained may be poured into water to form glass granulates and the glass granulates obtained are melted again.
For those skilled in the art it is understandable that the lithium oxide-silicon dioxide system has been extensively studied and several patents for dental glass ceramics have been granted in the last few years. However all the research so far falls in the range where lithium disilicate is formed as a final product and none of the references above disclose lithium silicate glass ceramic as a final product. For those skilled in the art it is evident that the type of crystal produced depends exclusively on the molar ratio of silicon dioxide to lithium oxide in the glass ceramic and not the additives or modifiers added to the mixture. This molar ratio controls the type of crystal formed in the final composition and furthermore give its name to the final glass ceramic.
Most of the existing patents in the dental field use the same basic components. The present invention uses germanium dioxide as a fundamental part of the formula. This oxide is broadly used in glass preparation for its good optical properties. The oxide has been well studied and has positive effects compared to common silicon glasses. It has been found that the addition of germanium oxide produces a melt with low viscosity, which facilitates the castability of the process and increases the thermal expansion and the refractive index of the resulting lithium silicate glass ceramic. More importantly, the addition of germanium dioxide increases the final density of the glass resulting in higher values of flexural strength than the lithium disilicate glasses free of germanium dioxide. U.S. Patent Application Publication No. 2004/0197738 to Ban et al. discloses a process to make dental frame of zirconium-yttrium sintered ceramics and they describe dental porcelain with germanium oxide as a joint component different than the zirconium yttrium oxide frame. However germanium oxide is not used as a component of the framework ceramic network. It is used only in formulation of the ceramic joint and is just a part of a series of other oxides that can be joined to the framework material.
Due to the low silicon dioxide to lithium oxide molar ratio of 1.7 of the present invention, equivalent to 37% molar of lithium oxide (63% silicon dioxide) the ceramic has a lower melting point compared to the glass ceramic of the prior art. In addition, this new glass ceramic contains the lowest silicon dioxide weight percent compared to all of the noted prior art. Therefore, due to this specific composition of lithium oxide in the mixture, the type of resulting crystal after crystallization (lithium silicate) gives to the glass ceramic its own chemical and physical properties, which makes it completely distinguishable from the prior glass ceramics listed above. Due to this distinguishable composition, the present glass ceramic has a lower melting temperature and can be made even lower with the addition of germanium oxide. Germanium oxide replaces silicon dioxide in the glass network, causing it to have a negative effect on the resulting melting point compared to a glass ceramic containing only silicon dioxide. Thus the processing and optimal melting temperature is in the range of 1100° C. to 1200° C. instead of 1200° C. to 1650° C. of the U.S. patents cited above and specifically compared to U.S. Pat. No. 6,514,893 to Schweiger et al. The glass ceramics listed in the prior art patents cannot be cast in the range of 1100° C. to 1200° C. because they are too viscous due to their high silicon dioxide content, therefore the processes disclosed in prior art patents with higher melting temperatures should be used. The present process will result in a more economical production because the energy employed for melting the glass is considerably lower and there are lower energy losses by radiation compared to the Schweiger process.
In addition to having a process with lower energy consumption, another significant improvement of the inventive process is related to the mixing and reaction of the components. In all of the previously cited prior art patents, the mix of the components is blended and melted at 1400 to 1650° C. and then cast or quenched in water. The quenched glass powder is dried, milled, and melted again in order to improve the homogeneity and the quality of the product. Surprisingly, it was found that the first melting and casting process can be avoided if one performs a calcination process on the mixture of raw materials to a temperature in the range of 700 to 800° C. without melting the components. At this stage, all the raw materials in the form of salts (like lithium carbonate as the source of lithium oxide, calcium carbonate as the source of calcium oxide, and di-ammonium phosphate as the source of phosphorous oxide) are decomposed, eliminating gases such as carbon dioxide and ammonia, producing a ceramic powder free of gases. After cooling down, the calcined mix is milled again, producing a homogeneous powder with a very small particle size. The final step is melting and casting in the range of 1100° C. to 1200° C., resulting in a homogeneity of all the components. In addition, by eliminating the gases during the calcination process, the glass cast becomes bubble free, making this a significant advantage over the processes described in the prior art.
The present invention is also unique compared to those listed in the prior art due to its composition. The use of a low melting temperature is only possible with the present glass ceramic because of the low content of silicon dioxide and the high content of lithium oxide. This translates to a molar oxide ratio (SiO2/Li2O) below 2.0, (i.e., 1.7) in which only lithium silicate crystals are produced (SiO2—Li2O). In addition to the composition, the present invention implements a process for a glass ceramic that produces a homogeneous product and that can be used only with the specific formulation. This process cannot be used with the other listed glass ceramics due to the lower operating temperatures.
The present invention emphasizes that in the inventive glass ceramic the silicon dioxide and lithium oxide molar ratio content (SiO2/Li2O) is less than 2, specifically the oxide molar ratio is preferably about 1.7. This is specifically equivalent to 63% molar of silicon dioxide and 37% molar of lithium oxide, and specifically equivalent in the overall formulation of about 56% weight percent of all of the glass ceramic as silicon dioxide and 16.0% weight percent as lithium oxide and the remaining 28% composed of the oxide additives and modifiers. In all of the glass ceramic, only lithium silicate (Li2O—SiO2) crystals are produced as the final crystal phase product. During the heating process of the glass, the first crystals formed are stable lithium silicate and they remain stable through the end of the growing process. This means that there is no need for a third thermal process for producing the final crystal of lithium silicate making this an additional characteristic unique to the present invention. This new ceramic has softening temperature of about 700 to 800° C. and a linear thermal coefficient of expansion of about 12 to 12.5×10−6/° C. as a final product and a composition yielding completely different chemical and physical properties compared to the prior art. This is easily demonstrated in commonly assigned U.S. patent application Ser. No. 12/592,825, paragraph [0012], FIG. 1 showing a XRD pattern diffraction where only lithium silicate crystals are present in the final product and paragraph [0013] where the glass ceramic has a percentage linear change of 0.55% measured at 500° C. and an equivalent coefficient of thermal expansion of 11.5×10−6/° C.
The following is a list of non-patent references noted herein:    1. MARCUS P. BOROM et al, Strength And Microstructure In Lithium Disilicate Glass Ceramics, J. Am. Ceram. Soc., September-October 1975, Vol. 58, No. 9-10, pp 385-391. The authors prepare lithium disilicate glass ceramics and measured the differences between the thermal expansion of the lithium disilicate with a value of 13×10−6/° C. and lithium silicate with a value of 11.4×10−6/° C. After the heat treatment above 800° C. the only phase present is lithium disilicate for a glass ceramic composition of 71.8% of silicon dioxide and 12.6 of lithium oxide.    2. R. A. EPPLER, Glass Formation And Recrystallization In The Lithium Metasilicate Region Of The System Li2O—Al2O3—SiO2, J. Am. Ceram. Soc., February 1963, Vol. 46, No. 2, pp 97-101.    3. F. A. HUMMEL, Thermal Expansion Properties Of Some Synthetic Lithia Minerals, J. Am. Ceram. Soc., August 1951, Vol. 34, No. 8, pp 235-239.    4. LANDOLT-BORNSTEIN (LB), Group IV Physical Chemistry—Phase Equilibria, Crystallographic And Thermodynamic Data For Intermediate Compounds in the Li2O—SiO2 System.    5. S. CLAUS et al, Phase Equilibria In The Li4SiO4—Li2SiO3 Region Of The Pseudobinary Li2O—SiO2, Journal of Nuclear Materials, Vol. 230, Issue 1, May 1996, pp 8-11.    6. HERMAN F. SHERMER, Thermal Expansion Of Binary Alkali Silicate Glasses, Journal of Research of the National Bureau of Standards, Vol. 57, No. 2, August 1956. The author prepares lithium silicate glasses with silicon oxide and lithium oxide molar ratio below 2.0 being lithium silicate with thermal expansion between 12 and 14.77×10−6/° C. There is no lithium disilicate using this chemical molar composition.

This patent is subject to a terminal disclaimer.

Lithium silicate glass ceramic for fabrication of dental appliances

James R. Glidewell Dental Ceramics, Inc.


A liquid crystal display device comprises a light source, a liquid crystal display cell and a light source liquid crystal cell having color filters, so that the light from the light source passes through the light source liquid crystal cell and the liquid crystal display cell for display wherein the light passing through the color filters in sections turns ON or OFF the liquid crystal at the sections on the color filters in sections at a great speed.

1. Field of the Invention
The present invention relates to a color display device using liquid crystals.
2. Description of the Prior Art
Currently used in the most common method for displaying color in a liquid crystal display are color filters for the three primary colors--red, blue, and green--which are provided for each of the picture elements in a liquid crystal display cell. Specifically, three picture elements are constructed to form one unit, in which the color to be displayed--red, blue, and green--in the respective picture element is predetermined, and, making use of the fact that the human eye is unable to distinguish the respective color elements, the method provides a total color harmony of the three colors in the display through the picture elements. For example, when the color to be displayed is white, the red, blue, and green picture elements are all displayed. Because the human eye is unable to differentiate between the respective three picture elements, the total of the three colors appears as white.
In this method, the color filters are usually provided inside the liquid crystal display cell. This is because, if they were provided on the outside of the liquid crystal display cell, the view would change according to the viewing angle.
This method has some drawbacks that the structure is complicated because one filter is provided for one picture element, that because three picture elements--red, blue, and green--are combined as one unit, the display is rather coarse, and that because the intensity of light for each color must be even, the thickness of the filters is not necessarily uniform, resulting in that the thickness of the liquid crystal layer is uneven.
In the case of TN type liquid crystal a slight variance in the layer thickness has no effect on the display, but in the case of a ferroelectric liquid crystal, even a slight variance in the thickness of the layer will affect the display.
Accordingly, there are existing problems to be solved in conventional liquid crystal display devices with respect to two features of picture quality and simplification of the manufacturing process.

Semiconductor Energy Laboratory Co., Ltd.


The present disclosure discloses an industrial internet of things with a dual front sub platform and a control method, the industrial internet of things includes a user platform, a service platform, a management platform, a sensor network platform, and an object platform that interact in turn. The service platform adopts a centralized layout, and the management platform and the sensor network platform adopt a front sub platform layout. The control method is used for the industrial internet of things.

In the field of product intelligent manufacturing, the intelligent product production line involves a plurality of intelligent manufacturing equipment. A plurality of intelligent manufacturing equipment are set according to a relationship of upstream and downstream, and the parts, components, or products to be manufactured are assembled in turn to form products. In the prior art, the upstream and downstream intelligent manufacturing equipment needs to comprehensively consider the unit product manufacturing capacity of each intelligent manufacturing equipment. For example, when the unit time manufacturing capacity of the upstream equipment is five, the unit time manufacturing capacity of the downstream equipment is better to be greater than or equal to five, so as to prevent the workpiece manufactured by the upstream equipment from accumulating to the downstream equipment and may not be digested in time. If the unit time manufacturing capacity of the downstream equipment is less than five, it may cause the upstream equipment to suspend operation (generally, it may not be shut down, due to shutting down and restarting, some equipment consumes high energy and takes a long time, which also needs preheating, pre-regulation, etc., causing that cost is high and working hours are long). It may not be operated again until the downstream equipment completes the production of accumulated workpieces, resulting in a large amount of no-load time for the upstream equipment. When the upstream equipment stops operation, the upstream equipment also makes corresponding adjustments, resulting in the adjustment of product manufacturing capacity in the whole production line, which affects the progress and orderly cooperation of the whole process.
In practical application, when the specified production capacity of the product may not be completed within the specified time, it is generally necessary to increase the manufacturing capacity of workpieces in each link. Therefore, it requires to consider how to adjust the overall production capacity of the equipment in each link without exceeding a maximum production capacity of the equipment in each link. The processes of processing and manufacturing of accessories, parts, components, and other structures required by the product are more and more complex, which involves the overall coordination of different workshops, different processes, and different equipment, the amount of data involved is huge and data types is more, the existing internet of things can not meet such a complex and cumbersome application environment and data processing. As a result, in the prior art, the assembly line may only be processed and divided into several small sub areas according to workshops, processes, or different parts for separately controlling, which cannot achieve overall coordination, and the manager cannot regulate and manage the output of all production equipment of the product as a whole.

Industrial internet of things with dual front sub platform and control methods thereof

CHENGDU QINCHUAN IOT TECHNOLOGY CO., LTD.


Preparation of 3-pentenoic acid by the reaction of 3-pentenoylchloride, water and butadiene. 3-chloro-1-butene and 1-chloro-2-butene are also formed. Preferably the 3-pentenoylchloride is formed by the reaction of chlorobutene with carbon monoxide using a palladium catalyst.

The preparation of 1-chloro-2-butene by the reaction of butadiene and hydrogen chloride is taught in U.S. Pat. No. 3,055,954 to Montagna et al.
The reaction of acyl halides with water to form acids is taught in standard organic chemistry textbooks.
The preparation of unsaturated carboxylic acid halides by the reaction of 1-chloro-2-butene (crotyl chloride) and carbon monoxide and a palladium catalyst is taught in U.S. Pat. No. 3,338,961 to Closson et al. See example 8 in particular. In example 5 the patent shows evaporation under vacuum prior to distillation of the product. Journal of the Chemical Society, 1964, pages 1588-1594, describes the use of palladium chloride complexes to react 3-chloro-1-butene with carbon monoxide to form 3-pentenoyl chloride. See table 2, page 1589.
3-pentenoic acid is an intermediate in the preparation of adipic acid from butadiene. See Burke U.S. Pat. No. 4,788,333. Adipic acid is a monomer used in the preparation of 6,6 nylon.
It is an object of the present invention to provide a process for the production of 3-pentenoic acid and 3-chloro-1-butene and 1-chloro-2-butene by a process in which less yield loss due to the formation of chlorovaleric acid than is obtained when these desired products are formed in separate reactions.

Preparation of 3-pentenoic acid and a catalyst therefore


A measured voltage drop across a power-line transistor is used as a sensing element to measure the current and detect an over-current condition for an LED backlight system. An over-current or short condition is detected when the measured voltage drop exceeds a threshold. Accurate detection of the over-current condition is achieved by calibrating the RDS-ON (i.e., internal resistance between drain and source, when transistor is on) of the power-line transistor. In one embodiment, the calibration of RDS-ON is performed by ramping down the threshold from an initial value and using the tripped threshold to determine the actual value for RDS-ON. In another embodiment, the calibration of RDS-ON is performed by using two thresholds, a first threshold to calibrate RDS-ON and a second threshold to detect the over-current condition.

LED backlight chips with a boost converter often utilize a power-line FET (field effect transistor) to switch off the current from the supply when the chip is off. It is also necessary to protect against high current conditions created by a short circuit at the output. The power-line FET can be used to limit the current flow during the initial in-rush period and also to protect against output short circuit fault conditions.
Various short circuit detection methods are commonly used which utilize either a sense resistor or a replica device. These methods require additional components and also add to the system power loss. It is also possible to use a component already existing in the current flow path and use its impedance to measure current and detect an over-current condition. Because of the variation of the sensing element's impedance from one component to the next, these methods usually lack accuracy.
As such, it is desirable to have a method to improve the accuracy of short circuit detection in LED backlight chips using the resistance of a component already existing in the current flow path to detect an over-current condition.


A processing method, which includes receiving a photographing instruction in order to trigger a camera to photograph a target document, identifying four sides of a document image corresponding to the target document, determining a first included angle corresponding to the document image, where the first included angle represents an inclination degree of the document image relative to the target document, triggering the camera to reset a focus location in a direction of far-end content in the document image, and taking n pictures when the first included angle is greater than a preset threshold, applying geometric correction to the pictures obtained through photographing, outputting one of the pictures to which geometric correction has been applied. Hence, the method significantly increase definition of the far-end content in the document image, and improve correction quality of the document image.

A user may take a photograph or record a video by using a mobile device having a photographing function (for example, a camera, a mobile phone, a wearable device, or a network camera). For example, in a conference room, people may photograph, at any time, information on a whiteboard, a slide, a document, or another material by using a mobile phone, and do not need to write down the information. This is quite convenient.
However, when such a mobile device is used to photograph an object, there is usually a specific included angle between an image plane of a camera and a photographed plane due to limitation of a factor such as a photographing distance or angle. This leads to relatively large image distortion. For example, a to-be-photographed object that is actually rectangular is possibly distorted into an arbitrary quadrilateral, such as a trapezoid. Such distortion is referred to as oblique distortion.
FIG. 1A and FIG. 1B show document images that are corresponding to a rectangular document and that have oblique distortion. Referring to FIG. 1A, the distorted document image is photographed at a relatively small inclination angle. The document image shown in FIG. 1A is an arbitrary quadrilateral rather than a rectangle. In addition, a font of a far-end character is smaller than a font of a near-end character. Worse, referring to FIG. 1B, the distorted document image is photographed at a relatively large inclination angle. Compared with the document image shown in FIG. 1A, a shape of the document image shown in FIG. 1B is even less like a rectangle. In addition, a far-end character in the document image shown in FIG. 1B is quite fuzzy and is difficult to recognize.
With respect to oblique distortion, some existing smartphones provide a document correction function in a photographing function.
The document correction function can well correct a distorted document image that is obtained through photographing at a relatively small inclination angle (for example, less than 15°). However, for a distorted document image obtained through photographing at a relatively large inclination angle (for example, greater than 50°), far-end content of a document image corrected by using the existing document correction function has relatively low definition.