A method and apparatus for sealing a combustion intake for a boiler from inside air is provided. A method and apparatus for providing a transition piece for venting fresh air to and combusted gas away from a boiler is also provided. A method of connecting a transition piece to PVC, ABS OR CPVC ductwork is also provided.

Domestic boilers are used to generate hot water, which may be used to flow through a circuit to provide heating to a facility such as a home or office building. The hot water also may be stored in a hot water tank and used for hot water needs such as running a dishwasher, showers and other domestic hot water uses. Often domestic boilers are located in homes in non-living spaces. For example, they may be located in a utility closet, a basement, a garage, or in other parts of the home that is more associated with storage or utility than with a living space. When boilers are placed in storage or utility areas they are typically mounted on the floor.
Sometimes, for a variety of reasons such as limited storage or utility space, boilers may be located in living spaces within homes or apartments. In order to conserve space, the boiler may be mounted on a wall. There are several desirable features associated with a wall-mounted boiler, such as a small size and/or weight to facilitate the wall mounting. In addition, wall mounted boilers are often located in kitchens or other living spaces, and therefore it is desired that they have an attractive appearance. Most known domestic boilers are configured to be one or the other of a wall mounted boiler, or a floor mounted boiler. This provides a disadvantage in that it is not possible to use a single boiler type for the different applications of wall mounting versus floor mounting. Thus, there is a need for a boiler which is adaptable to a multi-position mounting whether it be wall or floor mounted.
As with any energy-consuming device, increased efficiency is always a goal. Some known boilers have reduced efficiency for a variety of reasons. For example, sometimes room air is used in the combustion chamber and burned and vented to the outside. This results in a loss of efficiency in that the room air which was used for combustion and then vented to the outside may have been first processed by a heating, ventilation, or air conditioning system. A more efficient use of energy would involve the use of bringing in unprocessed outside air for combustion and then venting the combusted outside air back to the outside, thus maintaining room air which has been conditioned within the home. Thus, it is desirable to provide a boiler that burns almost exclusively outside air rather than using room air for combustion.
Another factor which limits known boilers is that many heat exchangers used in boilers are cast iron. Many boilers limit the amount of cooling of the combustion gases because if the combusted gases are cooled too much, the water vapor present in the combustion gases (a byproduct of combustion) will condense and form a condensate which may corrode the cast iron heat exchanger. Thus, using a cast iron heat exchanger limits boiler efficiency because combustion gases must be limited in how much they can be cooled. Limiting the amount of heat harvested from combustion gases limits efficiency because heat is wasted when it is vented out with exhaust gases.
Another limitation of many boilers equipped with cast iron heat exchangers is that some of them use parallel flow configuration. This limitation is related to the restraint of the cooling of the exhaust gases as mentioned above. Parallel flow heat exchangers are a less efficient type of heat exchanger than a counter flow heat exchanger. Counter flow heat exchangers are often not used because they are so efficient that they cool exhaust gases to a temperature that is not acceptable. If counter flow designs are used in cast iron heat exchangers they may need to be controlled in order to maintain the exhaust gases within an exceptable range of temperature to a degree where they may loose efficiency and thus nearly lose the efficiency benefits of being a counter flow heat exchanger. Thus, there is a need for a boiler that is not limited to cooling exhaust gases to a temperature that maintain water vapor in vapor form.
Accordingly, it is desirable to provide a boiler which has an increased efficiency and is not limited to cooling exhaust gases to the temperature ranges that maintain water vapor in vapor form. It is also desirable to provide a boiler that is not limited to the use of parallel flow heat exchangers but can incorporate a counter flow heat exchanging design.
If a boiler is not limited in its cooling of exhaust gases, it will generate condensate as water vapor in the exhaust gases condenses. Accordingly, it is desirable to provide a boiler that can accommodate condensate forming in the boiler and/or can accommodate the corrosive effects of the condensate.
Efficiency may further be increased by pre-heating outside air before combusting it. Accordingly, it may also be desirable to preheat the outside air.
Another way in which efficiency may be lost in boilers is that the controller of the boiler is often in an on/off type control. When additional heating is required, the boiler turns on, when less heating is required the boiler turns off. This type of configuration of on/off control loses efficiency because turning the boiler on may create heating of hot water than is required. A boiler which may be controlled to increase and decrease output and be turned on and off is a more efficient design. In addition, a controller that monitors a variety of boiler conditions can make more accurate control manipulations to the boiler and thus increase its efficiency.
Accordingly, it is desirable to provide a boiler controller that monitors a variety of boiler conditions and controls the boiler to not just a on/off condition but rather on, off, increase or decrease boiler function.
Another desirable feature of nearly all manufactured goods, not just boilers, is to simplify the design. Simplified designs are more cost efficient in production and often require less maintenance than more complex designs. As previously mentioned, many known boilers use cast iron heat exchangers. These cast iron heat exchangers are often cast sections that are sealed and then bolted together. The multiple sections of the heat exchangers and the bolting together create complexity.
Accordingly, it is desirable to provide a heat exchanger without multiple sections, thus simplifying the heat exchanging design.
Simplifying a boiler design to permit more easy installation and maintenance of the boiler as also desirable. For example, location of the electrical connections in multiple places on the boiler complicates installation and maintenance of a boiler because service personnel have to hunt down electrical connections. Providing a boiler with easy connections to ducting and venting will also simplify boiler installation.
Accordingly, a boiler designed to simplify installation and maintenance is desired.

Method and apparatus for providing a transition connector to introduce outside air and vent flue for boiler combustion


The optical signal sampling apparatus and the optical signal monitor apparatus are configured of an optical combiner for combining an optical signal to be sampled and a sampling light pulse with each other and an electroabsorption modulator. The electroabsorption modulator has two optical terminals for inputting/outputting the light and a power supply terminal for applying the electric field to the optical path connecting the two optical terminals, and has such a characteristic that the absorption rate of the light propagating through the optical path changes in accordance with the magnitude of the electric field, the light emitted from the optical combiner is received by one of the two optical terminals, and the absorption rate is increased when the sampling light pulse is not incident while the absorption rate is decreased when the sampling light pulse is incident. Further, the apparatuses include a DC power supply for applying a predetermined DC voltage to the power supply terminal and an optical separator for selectively emitting the optical signal component to be sampled, of the optical signals emitted from another of the two optical terminals.

In constructing a network with an optical signal modulated by a data signal, the quality of the optical signal propagated on the network is required to be monitored by an optical signal monitor apparatus.
Generally, the optical signal monitor apparatus acquires the waveform information of the signal on a transmission path and by calculating a value indicating the signal quality from the waveform information, outputs the calculation result thereof. It is very difficult to acquire the waveform information by receiving, directly with a light receiver, the optical signal modulated by the data signal of a very high bit rate of several tens of Gb/s.
In view of this, the conventional optical signal monitor apparatus uses the equivalent time sampling scheme to acquire the waveform information of the fast optical signal.
In the equivalent time sampling scheme, as shown in (a) of FIG. 15, the optical signal P with the same waveform repeated at the period Ta is sampled, as shown in (b) of FIG. 15, with a sampling pulse S having the period Ts=N·Ta+ΔT the slight time ΔT longer than N times (N: integer) the period Ta thereby to acquire, as shown in (c) of FIG. 15, instantaneous amplitude values (instantaneous intensity) different by ΔT at successive positions in the repetitive waveform of the optical signal P.
The waveform P′ plotted by the envelope connecting the instantaneous amplitude values thus acquired is a waveform of the optical signal P enlarged by Ts/ΔT times on the time axis, and holds the features of the waveform of the original optical signal P.
With regard to the waveform information acquired by this equivalent time sampling, the probability distribution of the amplitude indicating one of the binary levels and the amplitude of another is determined, and by calculating the standard deviation thereof, the Q value indicating the signal quality can be obtained.
The aforementioned technique of the equivalent time sampling of the optical signal and calculating the Q value indicating the signal quality from the waveform information thus obtained is disclosed in Patent Document 1.
According to Patent Document 1, a bulk-type nonlinear optical member is used normally as an element for the equivalent time sampling of the optical signal.
This nonlinear optical member is generally low in sampling efficiency (the sampling efficiency using the wavelength conversion phenomenon, i.e. the wavelength conversion efficiency is −20 dB or less). A high S/N can be obtained for the waveform information of a strong optical signal, therefore, the problem is that a sufficient S/N cannot be obtained for the waveform information of a weak optical signal.
In view of this, the use is conceived of an electroabsorption modulator remarkably lower in transmission loss than the nonlinear optical member, i.e. substantially high in sampling efficiency as an element for the equivalent time sampling of the optical signal.
The electroabsorption modulator has such a characteristic that the absorption rate of the light passed through the optical path connecting two optical terminals is changed in accordance with the magnitude of the electric field applied in the light path. Only during the time when the optical signal is applied to one of the optical terminals and the electricity sampling pulse signal applied to a power supply terminal to input the sampling pulse signal, the absorption rate of the optical signal is reduced so that the optical signal is emitted from another optical terminal thereby to sample the optical signal.
This technique of sampling the optical signal by applying the electricity sampling pulse signal to the power supply terminal of the electroabsorption modulator is disclosed, for example, in Patent Document 2.
The electricity sampling pulse signal used in Patent Document 2, however, requires the high-frequency impedance matching, and it is very difficult to narrow the pulse width in stable fashion without ringing. This poses the new problem that the waveform information of the optical signal modulated at several tens of Gb/s as described above cannot be acquired with a sufficient resolution and a high accuracy.
Also, in the optical signal quality monitor apparatus using the equivalent time sampling scheme described in Patent Document 1, assume that an eye pattern is generated by superposing a predetermined number of bits of the acquired waveforms and subjected to a quality calculation process on the eye pattern. As long as the sampling period Ts fails to coincide with N·Tc+ΔT strictly, the time axis of the waveform superposed is gradually displaced, thereby posing another problem that the accurate quality calculation is impossible.    Patent Document 1: Japanese Patent No. 3796357    Patent Document 2: Jpn. Pat. Appln. KOKAI Publication No. 2004-222252    Patent Document 3: Jpn. Pat. Appln. KOKAI Publication No. 2002-368313; corresponding to U.S. Pat. No. 6,819,689

Optical signal sampling apparatus and method and optical signal monitor apparatus and method using the same


A peeping prevention structure, a display device and a display method are provided. The peeping prevention structure includes: a first electrode and a second electrode opposite to each other; a plurality of transparent columnar cavities between the first electrode and the second electrode, wherein a plurality of opening regions are defined between the plurality of transparent columnar cavities, and each of the plurality of transparent columnar cavities is filled with charged light-absorbing particles; wherein, the charged light-absorbing particles are configured to, under a control of an electric field between the first electrode and the second electrode, be uniformly diffused in the transparent columnar cavity or be concentrated at an end of the transparent columnar cavity.

With development of display technology, display devices such as mobile phones and computers have become more and more widely used. Generally, a display device has a wide viewing angle, and users at different viewing angles may learn information displayed by the display device. However, in some scenarios, a user hopes that the information displayed by the display device is not known by other surrounding users, that is, the display device is required to have a peeping prevention function.

Peeping prevention structure, display device and display method

BEIJING BOE DISPLAY TECHNOLOGY CO., LTD.


A stage apparatus includes a first movable stage that moves while holding an article, an electrical contact that is provided on the first movable stage, and a grounding device that comes into contact with the electrical contact and grounds the first movable stage when the article is not processed.

In a lithography process as one of the manufacturing processes of a semiconductor device, various exposure apparatuses that transfers a circuit pattern formed in a mask or reticle (hereinafter, referred to as reticle) to a photosensitive substrate, such as a wafer or a glass plate, on which resist (sensitizer) is coated, are used.
For example, as an exposure apparatus for a semiconductor device, with the reduction of the minimum line width of the pattern according to high integration of an integrated circuit (device rule), a reduction projection exposure apparatus that transfers the pattern of the reticle on the wafer at a reduced scale using a projection optical system is mainly used.
In the above-described exposure apparatus, after exposure to a predetermined shot region on the wafer is performed, exposure to other shot regions is sequentially repeated. Accordingly, an error in relative position between the projection optical system and the wafer is caused by vibration due to movement of a wafer stage (in case of a stepper), or a reticle stage and wafer stage (in case of a scanning stepper). Then, the pattern is transferred at a different position on the wafer from a position corresponding to a design value. Therefore, if a vibration component is included in the positional error, image blurring (increase in pattern line width) may be generated.
Generally, a power supply member that supplies various kinds of power, such as a cable that supplies electric power to a driving unit such as motors disposed in the stage, a coolant pipe that cools the motors, a coolant pipe that keeps the stage at a predetermined temperature, a vacuum pipe that exhausts a vacuum absorption hole provided at a substrate placing surface to vacuum, is connected to the above-described stage (hereinafter, the cable and pipes are collectively referred to as cables). Then, fine vibration is caused by a tension applied according to the movement of the stage, and the reaction force thereof. Accordingly, precision of the pattern transfer may be degraded.
In Patent Document 1, there is disclosed a configuration in which a battery is mounted on a stage. Here, when the stage is provided at a wafer replacement position, a power transmission terminal provided in a base structure and a power receiving terminal provided in the stage are brought into contact with each other, such that the battery is charged with a current to be supplied from the power transmission terminal through the power receiving terminal. Further, when the stage is spaced apart from the wafer replacement position, a predetermined processing is performed using electrical power from the battery.
With this configuration, electrical wiring lines to the stage are not needed during a predetermined processing, such as an exposure processing or the like. Accordingly, dynamic and static characteristics of the stage can be improved.
Patent Document 1: Japanese Patent Application, Publication No. H10-270535


The present invention relates to a use of an effective amount of at least one probiotic microorganism and/or a fraction thereof and/or a metabolite thereof for preventing and/or treating dandruff disorders of the scalp, as well as a cosmetic process for preventing and/or treating a dandruff condition including the administration a first cosmetic active agent and of at least a second cosmetic active agent, topically, the said first and second cosmetic active agents being formulated in separate compositions, the first cosmetic active agent being chosen from probiotic microorganisms, and mixtures thereof, and the second cosmetic active agent being chosen from antidandruff active agents.

1. Field of the Invention
The present invention aims principally to propose a new active agent for the prevention and/or treatment of scalp disorders, especially aesthetic disorders. In particular, the present invention relates to dandruff disorders of the scalp, in particular of a greasy scalp. The present invention is also directed towards proposing a novel cosmetic process for preventing and/or treating a dandruff condition of the scalp. The present invention also relates to an assembly or kit that is suitable for use in a process of the invention. The present invention also relates to the field of topical products, food supplements or functional foods intended for scalp care.
2. Discussion of the Background
The scalp is an epidermis that undergoes continual renewal, like the rest of the cutaneous tissue, and that is rich in sebaceous glands. Normally, the scalp is renewed by imperceptible, non-visible elimination of the superficial skin cells. However, excessive renewal of the cells of the stratum corneum of the scalp, for various reasons, may result in the formation of large, thick patches of cells which are visible to the naked eye, known as "dandruff".
Various factors may promote the onset of dandruff. For example, mention may be made of stress, the winter period, an excess of sebum, a hydration defect or colonization of the skin or of the hair follicles by yeasts of the Malassezia spp. type. These factors especially have the common feature of causing or promoting skin inflammation. Such an inflammation reinforces the appearance or even increases the presence of dandruff.
The Malassezia sp. genus is constituted of lipophilic yeast normally present on human skin and on the skin of certain warm-blooded animals. The distribution thereof depends on age, on sebaceous gland activity and on certain pathologies. The Malassezia sp. yeast represents approximately 45% of the normal commensal flora at the surface of the scalp in individuals without dandruff, but can represent 75% of the flora in the case of dandruff, and up to 85% in the case of associated seborrhoeic dermatitis. The other microorganisms present at the surface of the scalp are micrococci and Propionobacterium. Imbalance of the scalp ecoflora is a factor that promotes or even reinforces the presence of dandruff.
Dandruff conditions are chronic, frequent, recurring conditions that are socially incapacitating owing to their obvious unattractive nature. Many factors can amplify these phenomena and result in the appearance of additional disorders, such as inflammatory conditions of the scalp. These dandruff conditions and/or inflammatory conditions of the scalp are reflected by an impairment of the barrier function of the epidermis. What is more, these conditions may give rise to sensations of itching or pruritus, resulting in scratching behaviour which amplifies the phenomenon of appearance of the dandruff.
The dandruff conditions of the scalp may be of greasy or oily type or of dry type.
The dry dandruff conditions of the scalp are more frequently manifested and are amplified during skin hydration disorders, and especially during substantial dryness of the epidermis of the scalp. Thus, the treatment of dry dandruff conditions, and the solving of the unattractive manifestations thereof, involve being able to sufficiently rehydrate the scalp.
Besides, as indicated above, the scalp is rich in sebaceous glands. It has been observed that dandruff develops more easily in the excessive presence of sebum and is more readily pruritic. Sebum secretion is a normal phenomenon which is useful for the skin and for the head of hair. Sebum protects the scalp and gives the hair a sheen by lubricating the cuticle. However, hypersecretion of sebum, or seborrhoea, may lead to disruptions, annoyances, sensations or feelings of discomfort, aesthetic disorders, or even a skin pathology. Thus, an excessive secretion of sebum promotes the appearance of a greasy or oily dandruff condition of the scalp or greasy or oily dandruff.
It has also been recently demonstrated that yeast of Malassezia type have a substantial lipase activity, resulting in the hydrolysis of sebum triglycerides so as to give fatty acids. These fatty acids are then capable of causing dandruff conditions in sensitive individuals, i.e. individuals having an impaired barrier function, and therefore more particularly susceptible to the destructive action of fatty acids on the cutaneous barrier.
Thus, the greater the presence of sebum, the more readily oily dandruff develops. Moreover, it has a tendency to be more readily pruritic.
Dandruff conditions generally respond to various local or systemic treatments. For example, various preparations comprising antimicrobial agents or keratolytic agents or keratinization regulators are commonly proposed for treating dandruff conditions. In particular, preparations combining antifungal and anti-seborrhoeic agents have been proposed in order to treat severe dandruff conditions, in particular greasy or oily dandruff conditions. The antifungal-based treatments demonstrate certain effectiveness on oily dandruff conditions.
However, the efficacy of these treatments is only suspensory and demands rigorous adherence on the part of the user (frequency of use and sufficient application time). Now, daily and long-term use of these treatments may lead to a phenomenon of dependence that reduces their efficacy. The dependence may be associated with a rebound phenomenon occurring when the treatment is stopped. The rebound phenomenon is generally manifested by hyperseborrhoea or pruritus, which are paradoxically liable to worsen the dandruff condition by impairing the barrier function of the scalp.
Moreover, the aggressiveness of certain antidandruff active agents with respect to the epidermal cells or the scalp ecoflora may also affect the scalp's barrier functions and lead to worsening of the dandruff condition.
Unpleasant side effects, such as heating or irritation phenomena, may also be manifested during the use of these treatments. These side effects may also be reflected by poor adherence to the treatments, thus reducing their efficacy.
In addition, most of the active agents usually used for treating dandruff often have an unpleasant odour that also reduces the adherence to the treatment.
Finally, the efficacy of antidandruff treatments is often slow to develop and requires rigorous application over the long term. This lag time often leads to failure to follow the treatment.
Consequently, many failures occur in the use of these treatments and can usually be attributed to the following factors: protocol not properly followed; frequency of use not adhered to; non-cosmetic appearance of the product; irritation by the washing base; application time not properly adhered to; lassitude.

Cosmetic use of microorganism(s) for the treatment of scalp disorders


The invention relates to a method for increasing the pressure of a liquid/gas multiphase fluid, and a method for compressing a gaseous fluid, comprising:

In a conventional hydrocarbon production installation, particularly offshore, the natural hydrocarbon reservoir is located in the subsoil. It consists of a volume of porous rock mainly comprising hydrocarbons in the gas and/or liquid state, and salt water. One or more wells are drilled to convey the fluids from the reservoir to the surface installations.
Hydrocarbon production is said to be flowing when the fluid pressure is sufficiently high within the reservoir to make the fluid rise naturally in the well and make the effluents reach the surface production units. However, in most cases, the flowing feature is absent, at least during part of the production period, particularly at the end of production. It is then necessary to artificially compress the fluids to make them rise to the surface and to operate at a requisite pressure.
In fact, conventional means for raising the pressure are only suitable for dealing with a single-phase fluid, that is, a gas or a liquid, but they are not suitable for dealing with a multiphase fluid, such as a petroleum effluent. Thus, pumps are known capable of raising the pressure of a gas-free liquid, and compressors are known capable of raising the pressure of a liquid-free gas.
In order to raise the pressure of a multiphase fluid of the petroleum effluent type, it is therefore necessary to separate the liquid and gas phases prior to their treatment, by a pump and a compressor respectively. Conventionally, the phases are separated using a tank or vessel, that is, a large volume unit in which the gas and liquid are separated by gravity. However, the operating pressure in a system of this type remains limited due to the large volume of a separation tank: this is because working at high pressure implies designing a tank with a very thick wall. This conventional system also has a number of drawbacks in terms of size and safety. It is particularly indispensable to provide safety depressurization means such as valves, vents or flares.
Other existing systems are installations called "WELLCOM" by CALTec which provide a compression of the hydrocarbon effluents issuing from low pressure wells using hydrocarbon effluents issuing from high pressure wells and achieve this in jet pumps or ejectors. A separation in a compact separator is provided in the case in which the effluents are multiphase, in order to compress the liquid with the liquid on the one hand, and, optionally, the gas with the gas on the other hand. If a high pressure well is lacking, the liquid portion can be compressed before serving in its turn to increase the pressure of the gas portion in a jet pump.
Document SPE 48934 (Carvalho et al., SPE Annual Technical Conference and Exhibition, September 1998) describes the combination of an electric submersible pump (ESP) and a jet pump in a hydrocarbon well. The ESP compresses the liquid hydrocarbons, and the gaseous hydrocarbons are entrained by the compressed liquid hydrocarbons using the jet pump.
Furthermore, document WO 2006/010765 describes a system comprising an "in line" separator upstream of distinct compressors for the gas, oil and water. The fluid residence time in the separator is short, so that this system is unsuitable for operation in slug flow conditions.
Another drawback of some of the abovementioned systems is associated with the mechanical transmission which is positioned on either side of the chamber walls, to apply forces to the fluids, said transmission raising a potential safety problem.
Besides these separate compression systems, other devices exist for raising the pressure of a multiphase fluid without separating the fluid phases. These include multiphase pumps. However, these devices remain complex and costly. This is because they require inlet fluid pretreatments to guarantee a minimum proportion of liquid, as well as cooling equipment, which accordingly demand safety equipment. They involve bulky, massive technologies, whose implementation entails a large scale design and manufacturing process. Their use also demands complex maintenance. They further often comprise rotating seals (mechanical seals), which are potential sources of gas leakage.
A need therefore exists for a method and a device for easy implementation thereof, for compressing a multiphase fluid to a high pressure, and which does not have the abovementioned drawbacks. In particular, a need exists to be able to adapt the capacity of the device to the evolution of the reservoir.

Method and device for compressing a multiphase fluid

Abstract: (b1) entrainment of the gaseous fluid using a motive liquid, to obtain a pressurized mixture of gas and motive liquid;

Abstract: (b2) separation of the pressurized mixture obtained in the preceding step in order to obtain, on the one hand, a compressed gas, and on the other hand, an auxiliary liquid.

Abstract: The invention further relates to devices for this purpose.

Abstract: Application to the production of hydrocarbons.


An attachment, adapted to mount to the front edge of an excavating bucket, includes a working structure and a base. The front edge of the bucket defines an inner surface, an outer surface, and a beveled surface oriented at an inclination to the inner and outer surfaces. The base of the attachment includes a single leg or pair of legs having opposed engagement surfaces. The engagement surfaces on the two legged attachments diverge from one another to define a gap therebetween for receiving the lip of the bucket. One of the engagement surfaces defines a convex surface which enables the attachment to be mounted to a variety of different buckets irrespective of the inclination of the beveled surface of the front edge.

Excavating buckets are used extensively in the construction and mining industries. Buckets are used with a variety of different excavating apparatus, such as back hoes, power shovels, front end loaders, dragline equipment, etc. Although these buckets have many differences, they are generally formed with a rear wall, side walls and a bottom wall. The walls cooperatively define an open front and a cavity for gathering earthen material and moving it to a dump site. The bottom edge of the open front is defined by a forward lip of the bottom wall. The lip is intended to engage the ground for collection of the material into the bucket's cavity. The lip may be formed to have a linear or arcuate shaped edge, or formed to have a particular configuration (such as V-shaped) to suit the desired operation. Similarly, the front edges of the side walls are also adapted to engage the ground.
Attachments are commonly mounted on the lip and the front edges of the side walls to increase the effectiveness and durability of the buckets. These attachments typically include teeth, shrouds and wings. The teeth project forwardly of the lip to disrupt the material for enhanced collection of the material into the cavity. The shrouds are positioned in between the teeth and are generally provided with an inclined surface to improve the collection of the material into the bucket. The wings are attached to the front edges of the side walls in general proximity with the lips. In any event, the attachments protect the bucket against undue wearing. As a result, only the attachments normally need replacement when the front of the bucket becomes worn; thus, prolonging the usable life of the larger and more expensive lip and side walls.
In most cases, a tooth is formed of an adapter and a point. The adapter is attached to the lip and serves as a mount for the point. The point is a wear element and forms the forward portion of the tooth that engages the ground. The point may be attached to the adapter in a number of different ways. Examples of such arrangements are disclosed in U.S. Pat. Nos. 4,231,173 to Davis, 4,335,532 to Hahn et al., and 4,727,663 to Hahn. As a result of this two-part construction, replacement of only the point is generally needed when the tooth becomes worn.
The attachments are each formed with a forward working portion and a rearward mounting portion. The forward working portions of the adapters include structures to facilitate attachment of the points. The forward working portions of the shrouds and wings typically include surfaces designed to engage the worked material and guide it into the bucket. The rearward portions of the attachments are typically bifurcated to define a pair of legs. The bifurcated legs straddle the lip so that one leg lies against the interior of the bucket and one leg lies against the exterior thereof. In some bifurcated designs one leg extends only a very short distance rearward of the lip edge. Alternatively, some designs have only one leg that lies against the interior of the bucket. In any event, the legs generally have hollow central portions to provide greater weight reduction. As a result of this hollowed construction, a peripheral rim is defined around the legs for engaging the lip.
The attachments can be secured to the bucket in a number of different ways. For instance, the attachments may be secured through the use of a wedge locking system, such as disclosed in U.S. Pat. Nos. 4,267,653 to Hahn et al. and 4,271,615 to Jones. Alternatively, the attachments may be secured to a lip by welding or bolting.
The lips and side walls of different buckets are not generally uniform in shape and are often manufactured with leading beveled edges which are oriented at different inclinations. The leading beveled edge is an inclined surface at the forward end of the lip or side wall, which lies in a plane intersecting the exterior and interior surfaces. The inclination is upwardly and rearwardly with respect to the outer surface. Hence, irrespective of the type of mounting arrangement used to secure the attachment to the bucket, a unique attachment is ordinarily required for each different bucket to accommodate the different configuration. This special manufacturing of the attachments not only increases fabrication costs, but also creates a substantial inventory for users and distributors.


A method for file handling in a hierarchical storage environment includes receiving a new document for storage, and triggering and/or initiating a new document notification process upon receipt of the new document. The new document notification process includes scanning the new document for a set of keywords and/or references; creating enhanced metadata for the new document, wherein the enhanced metadata includes the set of keywords and/or references from said scanning; storing the enhanced metadata in a file system; and evaluating the enhanced metadata via a relationship analyzing process to produce a priority list defining a likelihood of possible access. The method also includes storing the new document in a storage tier of a hierarchical storage environment according to the priority list.

The present invention relates in general to the field of file storage management, and in particular to a method for file handling in a hierarchical storage environment and a corresponding hierarchical storage environment. Still more particularly, the present invention relates to a data processing program and a computer program product for file handling in a hierarchical storage environment.
The technical area of this invention concerns the overall enhancement of file storage management. This is in an area of tremendous growth hence technologies increasing the effectiveness are very valuable.
File access typically is provided through network attached storage (NAS) systems. Tiered data storage is a technique which automatically moves data between high-cost and low-cost storage media based on rules and policies.
A request to access data that was migrated from "higher" (faster) to "lower" (slower) level storage tier typically results in a longer response time; sometimes significantly longer response time. In some tiered storage environments this might involve recalling data from removable media such as tape. In such cases it usually takes several minutes, and even up to hours, before a user can access the data if all tapes drives are currently in use. For users trying to access this data, such long response times create a bad experience, and may be simply not acceptable in certain scenarios. One example is a student in a library trying to access a series of related articles and/or files via a console that have been moved to a lower level storage tier.
Retrieving files in tiered storage environments, especially files migrated to lower level storage tiers, may present several challenges. For instance, users expect immediate file access (and thus a good user experience), however it can take a long time to actually access the data due to the slower performance of lower level storage tiers or the slow performance associated with the recall process from removable media. Moreover, users often require access to multiple files, which may be content related independent from the actual storage location or storage tier; thus the overall response time may accumulate over multiple file access. Moreover still, while hierarchical storage environment or so called storage tiering may be used because of its cost effectiveness, it may not be economic to keep all data always in the highest level storage tier. Further, conventional solutions for file access in tiered storage environments may offer limited connection between a conventionally specified set (e.g. a prior art set) of metadata associated with a file and the probability that a file will be used again.

Method for file handling in a hierarchical storage environment and corresponding hierarchical storage environment

International Business Machines Corporation


A rear-projection screen comprises an optical unit, a light-blocking layer, and an optical lens. The optical unit has a first surface and a second surface. The first surface is opposite to the second surface. The first surface has a plurality of cylindrical convexes and the second surface has a plurality of irregular protruding parts. The light-blocking layer adjoins to the second surface and has a plurality of striped light-absorbing units. The optical lens is disposed adjacent to the optical unit.

1. Field of Invention
The invention relates to a rear projection screen and an optical device thereof and, in particular, to a rear projection screen and an optical device thereof, which can prevent the moiré effect.
2. Related Art
Rear projection televisions are generally applied to television teaching and training of real-sight simulation for pilots and drivers. However, with raising the living standards and improving the living conditions, the rear projection television becomes more and more favor to consumers. Rear projection television is characterized by its wide screen and clear image. Comparing with the conventional cathode ray tube (CRT) television, the rear projection television has the advantages of low irradiation and large screen dimensions, and can connect directly to the computer or other video apparatuses for achieving the maximum of entertainment effects. Therefore, it can be predicted that the rear projection television will play a major role in the market of the entertainment display in the future. In the rear projection television, the image is projected onto the real projection screen from rear side of the screen, and the viewers can obtain the image from the front side of the screen. As a result, there has been a demand for considering that the viewing angles, image contrast, image resolution, and image brightness and so on while one designs the rear projection television.
With reference to FIG. 1, a conventional rear projection screen 1, which is composed of a Fresnel lens 11 and a lenticular lens 12, is a transmissive screen. The Fresnel lens 11 can facilitate to properly utilize light within the visual area so as to raise the brightness and uniformity of image. The lenticular lens 12 is used to generate the image.
The lenticular lens 12 has a plurality of cylindrical convexes 121 formed on the light-incident surface and a plurality of black stripes 122 formed on the light-emitting surface. The incident light beams from the light source are focused in the Fresnel lens 11 and passed away as the parallel light beams, which are incident into the cylindrical convexes 121 later and are further focused. The black stripes 122 made of the light-blocking material are accurately formed in positions corresponding to non-focusing parts of the cylindrical convexes 121. The black stripes 122 formed on the light-emitting surface are used to absorb the light beams for reducing the interference of the outside light.
Generally, a plurality of the black stripes 122 disposed on the cylindrical lens 12 is manufactured as the following description. Coating a photoresist on a surface of the cylindrical lens 12, on which the black stripes 122 are to be formed. Next, the cylindrical convexes 121 is irradiated with light beams from a light source, so that the light beams can be focused with the cylindrical lens 12 on the photoresist. Then, the black stripes 122 is formed by positive development (or negative development) procedures. As the cylindrical convexes 121 are arranged regularly and have approximately the same curvatures and heights, the manufactured black stripes 122 are regular arranged and have the same widths. This may easily cause the interference effect, resulting in the so-called moiré phenomenon that reduces the quality of the image.
Therefore, it is a subjective of the invention to provide a rear projection screen and an optical device thereof, which relieve the moiré phenomenon of the conventional rear projection screen.

Rear projection screen and optical device thereof


The present invention relates to a tracking system comprised in a receiver, which tracking system is operable to track rapid changes in frequency and phase offset. The tracking system comprises a first system operable to perform a pilot-based phase and frequency tracking. The tracking system also comprises a second system operable to perform data-based phase and frequency tracking. The tracking system also comprises a control means connected to said first system and to said second system, which control means is operable to gradually reduce the effect of said first system, i.e. said pilot-based phase and frequency tracking.

A well-known issue in designing transceiver systems in which rapid transitions must be made between e.g. receive and transmit states or between idle and receive states, is that the local oscillators on the system can suffer a perturbation from their stable operating frequency. This can, for example, be due to a sudden change in load on the power supply. An example of such a glitch is shown in FIG. 1, related to the preamble of an IEEE 802.11 WLAN OFDM transmission. In FIG. 1, reference numeral 2 denotes the short preamble symbols, 4 denotes the cyclic prefix (CP) and the long preamble symbols, 6 denotes the SIGNAL field and 8 denotes the data symbols. The VCO frequency is shown initially at one stable level; when the transmission begins, the operating conditions change and the VCO moves to a different stable operating frequency. Since the VCO operates in a feedback loop, it takes time for the frequency to converge on the new stable operating frequency.
Although it may be possible to design ones own receiver to have an extremely stable VCO, it is impossible in an open market such as that for WLAN devices to be sure that competitors' devices have equally high standard for their transmitters. To be interoperable, it is therefore necessary to be able to compensate for such deviations.
In a typical WLAN receiver, an initial coarse estimate of the frequency offset will be made during the short preamble symbols. A more precise estimate will be made during the long preamble symbols. The changing frequency of the VCO means that the frequency estimates are likely to be inaccurate; and even if a fairly accurate frequency estimate has been made by the end of the long preamble symbols, the frequency is likely to change further.
The problems caused by a residual frequency error will be explained with reference to the operation of a simplified digital OFDM receiver datapath as shown in FIG. 2.
The first operation in the datapath is to correct the frequency error, which is achieved by a progressively phase rotation of the incoming I/Q samples, which is intended to exactly cancel out the phase rotation of the incoming signal due to the frequency offset. In the absence of any other input, the frequency correction is based on the initial frequency estimate.
This operation is performed in the frequency correction block 10.
The next operation is to perform a fast Fourier transform (FFT), at the block 12, on the received data. This separates the received time-domain symbol into a number of independently modulated sub-carriers. In an 802.11a OFDM transmission, there are 52 sub-carriers, of which 48 are used to transmit data and 4 are pilot tones modulated with a known sequence.
Next, the sub-carriers extracted by the FFT 12 are demodulated, at the demodulation block 14, (converted from symbols into [soft] data bits). In order to perform the demodulation, it is necessary to have an estimate of the channel transfer function for each subcarrier, which is represented by a scaling and a rotation of the transmitted constellation. The initial channel estimate is typically obtained during the long preamble symbols.
Finally, error correction, at the error correction block 16, is applied to the received data stream. In an 802.11 OFDM transmission, a Viterbi decoder is typically used to perform the error correction function.
D denotes the data outputted from the OFDM receiver.
A residual frequency error means that the frequency correction block will not completely remove the frequency offset. The first problem that this causes is that there is a progressively increasing phase rotation of the received signal at the output of the frequency correction block. The demodulation process is based on the received signal phase as estimated during the long preamble. The progressive phase rotation caused by the frequency error means that there will be an increasing phase error with respect to the channel estimate. At a certain point, this will lead to uncorrectable demodulation errors. An example of this is shown in FIG. 3: the unrotated received I/Q vector is shown as a solid line, and is near to the correct constellation point corresponding to the transmitted data. E denotes the correct constellation point for received vector and F denotes all of the ideal constellation points according to channel estimate. As the received vector is progressively rotated away from E, it is clear to see that at some point demodulation errors occur. To keep a reasonable degree of clarity in the figure, the example shown uses 16-QAM modulation; IEEE 802.11 OFDM transmissions also use 64-QAM for higher rate transmissions. Since 64-QAM has 4 times as many constellation points it is clearly much more sensitive to phase errors.
A second problem, caused by moderate to severe frequency estimation errors, is loss of orthogonality in the FFT. In the absence of a frequency error, the subcarriers are perfectly separable from one another (the energy from one subcarrier does not interfere at all with another subcarrier). However, if the frequency offset becomes at all large, a significant amount of inter-carrier interference occurs which is visible as noise in the signal at the demodulator.
If it is possible to measure the phase and frequency errors of the signal during reception, it is conceptually possible to correct for them. The phase error of a received I/Q vector can be estimated based on knowledge of the channel estimate and the transmitted constellation point, by directly measuring the angle from the expected constellation point and the actual received vector. This estimate is perturbed by errors in the channel estimate and by noise; an improved estimate for the phase can be obtained in an OFDM symbol by measuring the phase error over a number of subcarriers, possibly also with weighting according to the strength of the subcarrier signals.
The frequency error is simply the change in the phase estimate with time, and can be estimated by dividing the phase change between two symbols with the symbol period.
As mentioned, in order to estimate the phase and frequency error, it is necessary to know the constellation point corresponding to the transmitted signal. One possible solution to this problem is to use the demodulated data to try to determine the correct constellation point, using an architecture such as that shown in FIG. 4, called data-driven phase and frequency tracking. The corresponding function blocks in FIGS. 2 and 4 have been denoted with the same reference signs and will not be explained again. In FIG. 4 there is also disclosed a frequency estimation block 18 connected to the block 12 and to the block 10. Finally, there is also a remodulation block 20 connected to the frequency estimation block 18. Demodulated data can be taken at two possible locations: for greatest robustness, it should be taken at the output of the error correction block, since this ensures the minimum number of selection errors. However, it may also be taken from before the error correction block.
This demodulated data is then re-modulated (mapped back into I/Q constellation points) for each subcarrier in the OFDM symbol, based on the channel estimate. It is then possible to use all of the subcarriers in the OFDM symbol to make an estimate of the overall phase rotation of the OFDM symbol.
Typically, this phase error is used as an input to a PID (proportional, integral, derivative) control loop, which uses the instantaneous estimates for the phase and frequency error plus an integral phase term to drive the input to the frequency correction block, thereby simultaneously tracking errors in both phase and frequency.
As was mentioned earlier, an IEEE 802.11a OFDM transmission uses only 48 of the 52 subcarriers for carrying data. The remaining 4 pilot tones are modulated with a known sequence, and these can therefore be used directly for the measurement of phase error.
An example architecture is shown in FIG. 5, called pilot-based phase and frequency tracking. The corresponding function blocks in FIGS. 2, 4 and 5 have been denoted with the same reference signs and will not be explained again. In FIG. 5 there is also disclosed a phase correction block 22 connected to the block 12 and to the block 14. Finally, there is also a pilot-based phase estimation block 24 connected to the block 10 and to the block 22. The pilot-based phase estimation block extracts the pilot subcarriers from the data stream, and uses them to calculate an estimate of the phase rotation for the current OFDM symbol. This estimate of the phase error is then used by the phase correction block, which de-rotates the received symbol prior to demodulation.
It is also necessary to correct the frequency error in order to avoid loss of FFT orthogonality. This is done by estimating the residual frequency error based on the symbol-by-symbol rate of phase change, and feeding back this estimate to the frequency correction block, which adds the residual frequency error estimate to the correction frequency.
Data-driven frequency and phase tracking has the advantage that it maximises noise rejection by taking into account all of the available subcarriers in the signal. However, a major drawback is that, in order to obtain reliable data estimates, it is necessary to take the data from the output of the error correction block. This block has a large latency (usually several data symbols), which means that the frequency tracking loop is very slow to respond. For all but very minor residual frequency errors, the accumulated phase error will become so great that demodulation fails and the frequency tracking loop breaks down.
The pilot-based method is very robust, since the pilot tones are known in advance and the phase correction is applied immediately, and can therefore cope with large and rapid swings in frequency. The problem with the pilot-based solution, however, is the noise introduced by the phase estimate due to it being made over only the 4 pilot subcarriers. This noise directly modulates the received symbol, increasing the error vector magnitude and thereby the error probability.
Since large and rapid frequency deviations are observed only near the beginning of the transmission, it is desirable to be able to use robust pilot-based tracking near the beginning of the transmission, but to switch over to less noisy, but slower data-based tracking for the remainder of the transmission, using a combined architecture such as that shown in FIG. 6. The corresponding function blocks in FIGS. 2, 4-6 have been denoted with the same reference signs and will not be explained again. However, this is difficult to achieve in practice, due to the error properties of the pilot-based tracking method.
The phase estimate calculated from the pilot subcarriers has an accuracy that is adequate for demodulation. However, the frequency error is based on the slope calculated over two such noisy estimates, and is therefore much more prone to noise which causes random frequency deviations from the symbol to symbol.
When the pilot-based phase correction is being performed, the phase deviations from these random frequency deviations are corrected for. However, when pilot-based tracking is deactivated, the frequency correction block maintains the frequency error from the last estimate. Since the data-based frequency tracking loop has a latency of several symbols, the overall phase error increases in just the same way as happened with the original VCO frequency deviation, and will often cause failure before the frequency tracking loop can correct for the residual error.


Magnetic resonance imaging systems having gradient coil assemblies employing a liquid dielectric medium are provided. In one embodiment, a magnetic resonance imaging system includes a gradient coil assembly with a plurality of gradient coils. In the gradient coil assembly, at least two of the gradient coils are electrically separated from one another by a fluid medium.

The subject matter disclosed herein relates generally to magnetic resonance imaging systems and, more particularly, to cooling and electrically separating two or more gradient coils for magnetic resonance imaging systems.
Magnetic resonance imaging (MRI) systems enable imaging based on a primary magnetic field, a radio frequency (RF) pulse, and time-varying magnetic gradient fields that interact with specific nuclear components in an object, such as hydrogen nuclei in water molecules. The magnetic moments of such nuclear components may attempt to align with the primary magnetic field, but subsequently precess at a characteristic frequency known as the Larmor frequency. An RF pulse at or near the Larmor frequency of such nuclear components may cause the magnetic moments to be rotated. When the RF pulse has ended, the magnetic moments may attempt to realign with the primary magnetic field, emitting a detectable signal.
At least three discrete gradient coils (x, y, and z) may produce time-varying magnetic gradient fields (Gx, Gy, and Gz) calculated to enable detection of signals from a specified slice of the object. Because the gradient coils may be disposed near to one another, a partial discharge of voltage may occasionally occur between two of the gradient coils, which may cause any images then being acquired to display one or more artifacts. To prevent partial discharge, each generally cylindrical gradient coil may be electrically separated from the other by a glass-filled, epoxy-based resin. Such an epoxy-based material may have many drawbacks, including low partial discharge inception voltage (PDIV) characteristics, inefficient gradient coil cooling, and long manufacturing cycles due to the vacuum pressure impregnation procedure generally employed in the manufacture of epoxy-based gradient coils.

Liquid dielectric gradient coil system and method


A device for opening and closing injection nozzles in an injection moulding tool. The injection nozzle comprises a nozzle member, the nozzle opening of which can be opened and closed with a needle. The needle is stationarily arranged on a piston plate that is supported in a receptacle such that it can be moved in both axial directions similar to a double-action cylinder. A first work chamber is formed on the side of the piston plate which faces away from the needle and a second work chamber that can be acted upon with a fluid in order to actuate the needle is formed on the opposite side of the piston plate. The needle extends outward from the second work chamber through a recess in an end element that lies opposite of the piston plate. In this case, the second work chamber is sealed in an essentially fluid-tight fashion by means of a first sealing element that is arranged between the inner wall of the receptacle and the piston plate and a second sealing element that is arranged between the wall of the recess and the needle and comes in direct contact with the needle.

For example, devices of the type in question are, although not exclusively, utilized in so-called hot runner moulds, in which the moulding mass to be processed is injected into the mould cavity in a timed fashion via heated channels, valves and nozzles. In this case, the injection nozzles are typically realized in the form of needle valves or needle-type nozzles, in which the point of a needle is pressed against a seat in the nozzle member which is realized complementary with respect to the shape and function of the needle in order to close the nozzle and lifted off said seat in order to open the nozzle.
In one known device, the needle is stationarily arranged on a piston plate that is supported in a receptacle such that it can be displaced in both axial directions similar to a double-action cylinder, wherein a first work chamber is formed on the side of the piston plate which faces away from the needle and a second work chamber is formed on the opposite side of the piston plate, wherein the second work chamber can be acted upon with a fluid in order to actuate the needle, and wherein the needle extends outward from the second work chamber through a recess in an end element that lies opposite of the piston plate. One disadvantage of this known device can be seen in the fact that the piston plate has a comparatively large mass. If several needles are provided, the constructive design also results in a comparatively large spacing between the needles or injection nozzles.
Based on this state of the art, the invention aims to develop a device of the previously described type which has smaller moving masses and makes it possible to achieve a small spacing between adjacent needles and consequently several injection nozzles per surface unit.

Device for opening and closing injection nozzles in an injection moulding tool


An image signal reproducing apparatus includes a synchronizing signal generator which is configured so as to count the number of clocks of a generated clock signal, generate various kinds of timing signals in accordance with the result of count, compare the phase of the generated timing signal with the phase of an input synchronizing signal, and control a period to count the number of clocks of the clock signal in accordance with the result of comparison. It becomes thereby possible to form various kinds of correct timing signals even if the input synchronizing signal reproduced from a recording medium is deteriorated.

1. Field of the Invention
This invention relates to an image signal reproducing apparatus having a synchronizing signal generator for generating various kinds of timing signals in accordance with synchronizing signals recorded on a recording medium together with information signals.
2. Description of the Prior Art
There have been information signal recording and reproducing apparatuses in which synchronizing signals are recorded on a recording medium together with information signals when recording. The synchronizing signals recorded on the recording medium together with the information signals are reproduced when reproducing, various kinds of timing signals are generated in accordance with the reproduced synchronizing signals, and various kinds of processings are performed using the reproduced information signals in accordance with the generated timing signals.
In the above-described information signal recording and reproducing apparatuses, information signals to be recorded and reproduced are, for example, television signals.
As the current scanning method for television signals, a 2:1 interlaced scanning method is generally used in which scanning is performed by jumping every other scanning line. In the NTSC method, for example, interlaced scanning for television signals is performed so that scanning lines mutually interlace every 1/60 second, and a frame image for one picture frame is provided every 1/30 second using two field images each formed by a single interlaced scanning operation.
As described above, in the television signal in the NTSC method, one picture frame is provided by two field images. The single picture frame comprises 525 scanning lines.
A composite synchronizing signal (C.sub.sync) composed of a horizontal synchronizing signal (H.sub.sync) indicating one horizontal scanning period and a vertical synchronizing signal (V.sub.sync) indicating one vertical scanning period is added to the above-described television signal, and continuity of the synchronous signals is maintained at the boundary of consecutive field periods.
As an apparatus for recording the above-described television signals on a recording medium, such as a magnetic disk or the like, and reproducing the signals from the medium, there has been used a still video recording and reproducing apparatus,
In the still video recording and reproducing apparatus, a magnetic disk, serving as a recording medium, is rotated at a speed of 3600 rpm, an image signal for one field is recorded on one of a plurality of tracks concentrically formed on the magnetic disk, and the recorded image signal for one field is repeatedly reproduced to obtain a still picture image signal.
When reproducing the still picture image signal as described above, in order to conform to the above-described television-signal scanning method, an image signal for one field is delayed by 1/2 the horizontal synchronizing period (1/2 H) except for the vertical synchronizing period using a 1/2 H delay device, and an image signal delayed by the delay device and an undelayed image signal are output by being alternately switched at every one field period. Thus, a so-called skew compensation processing is performed which conforms to the above-described interlaced scanning while maintaining the continuity of the horizontal synchronizing signal.
FIG. 1 is a digram showing the schematic configuration of a conventional still video reproducing apparatus. The operation of the conventional still video reproducing apparatus will now be explained.
In FIG. 1, a magnetic disk 100 is rotated by a motor 101 at a speed of 3600 rpm. Signals recorded on tracks formed on the magnetic disk 100 by a magnetic head 102 are reproduced and supplied to a reproducing amplifier 103.
A signal reproduced by the magnetic head 102 is amplified to an amplitude level for practical use by the reproducing amplifier 103. The amplified signal is supplied to a demodulation circuit 104, whereby the signal is demodulated. An image signal for one field to which a composite synchronizing signal has been added is then output and supplied to a synchronizing signal separation circuit 105 and an image signal processing circuit 107.
The synchronizing signal separation circuit 105 separates the composite synchronizing signal from the signal supplied from the demodulation circuit 104. The separated composite synchronizing signal is supplied to a timing signal generation circuit 106 and a synchronizing signal addition circuit 108.
A magnetic piece (PG pin) 107 for detecting the rotation phase of the magnetic disk 100 is provided on a circumference on the core of the magnetic disk 100. Every time the PG pin 107 crosses over a PG coil 108 due to the rotation of the magnetic disk 100, a pulse signal is output from the PG coil 108. The pulse signal output from the PG coil 108 is subjected to waveform shaping by a waveform shaping circuit 109, and then is supplied to the timing signal generation circuit 106 as a PG pulse signal synchronizing with the rotation phase of the magnetic disk 100.
An image signal recorded on each track on the magnetic disk 100 is recorded so that the added vertical synchronizing signal is situated at a position deviated by 7H.+-.2H in the circumferential direction from the position where the PG pin 107 is provided.
The timing signal generation circuit 106 forms a blanking signal B and a skew compensation gate signal S in synchronization with the composite synchronizing signal supplied from the synchronizing signal separation circuit 105 and the PG pulse signal supplied from the waveform shaping circuit 109. The blanking signal B and the skew compensation gate signal S thus formed are supplied to an image signal processing circuit 110 and a change-over switch 113 (to be described later), respectively. The image signal processing circuit 110 performs horizontal and vertical blanking processings for the image signal supplied from the demodulation circuit 104 in accordance with the blanking signal B supplied from the timing signal generation circuit 106, and supplies the resultant signal to a synchronizing signal addition circuit 111.
The synchronizing signal addition circuit 111 adds the composite synchronizing signal separated from the synchronizing signal separation circuit 105 to the image signal for one field subjected to the blanking processings in the image signal processing circuit 110 in the preceding stage, and supplies the resultant signal to a 1/2 H delay circuit 112 and terminal "a" of the change-over switch 113. The 1/2 H delay circuit 112 delays the supplied image signal by a period of 1/2 H, and supplies the delayed image signal to terminal "b" of the change-over switch 113.
By alternately switching the connection between the side of terminal "a" and the side of terminal "b" at every one-field period in accordance with the skew compensation gate signal S output from the timing signal generation circuit 106, a frame image signal conforming to the interlaced scanning method is output from the change-over switch 113 via an output terminal 114.
FIGS. 2(a) and 2(b) show an example of the configuration of a synchronizing signal generator in the above-described still video recording and reproducing apparatus, and a timing chart indicating the operation thereof, respectively.
FIG. 2(a) is a diagram showing the configuration of a synchronizing signal generator for generating window pulses (H.sub.BLK) for providing horizontal blanking periods in the reproduced still-picture image signal in the still video recording and reproducing apparatus.
In the still video recording and reproducing apparatus, a signal C.sub.sync (see FIG. 2(b)) reproduced when reproducing is supplied to reset terminal RES of a counter 300 shown in FIG. 2(a).
The counter 300 is reset during a low-level period of the signal C.sub.sync supplied from the terminal RES, performs counting from a leading edge (T.sub.0 in FIG. 2(b)) of the signal C.sub.sync for a predetermined period (T.sub.2 in FIG. 2(b)), and supplies AND gates 301 and 302 with count data.
The AND gate 301 detects whether or not output count data from the counter 300 have reached T.sub.1 from T.sub.0 in FIG. 2(b), and outputs a high-level signal when data have reached T.sub.1. The AND gate 302 detects whether or not the output count data from the counter 300 have reached T.sub.2 from T.sub.1 in FIG. 2(b), and outputs a high-level signal when the data have reached T.sub.2.
Signals output from the AND gates 301 and 302 are supplied to set terminal S and reset terminal R of an S-R flip-flop 303, respectively. As a result, window pulses H.sub.BLK as shown in FIG. 2(b) are output from output terminal Q of the S-R flip-flop 303. In the still video recording and reproducing apparatus, horizontal blanking periods are provided in the still-picture image signal in accordance with the pulses H.sub.BLK formed as described above.
In the prior art as described above, however, a point to start recording for an image signal recorded on a magnetic disk and a horizontal synchronizing signal obtained from an image signal reproduced from the magnetic disk do not always maintain a constant phase relation. Furthermore, variations exist among reproduced magnetic disks in positional relation between the point to start recording of an image signal and the switching point between a signal delayed by 1/2 H from the image signal reproduced from the magnetic disk and an undelayed signal in skew compensation, that is, the position of a PG pin. Hence, when the signal delayed by 1/2 H from the image signal reproduced from the magnetic disk and the undelayed signal are switched at the position of the PG pin for the purpose of skew compensation, the phase between the point to start recording of the image signal recorded on the magnetic disk and the horizontal synchronizing signal obtained from the image signal reproduced from the magnetic disk is different for every magnetic disk.
FIG. 3, composed of FIGS. 3(a)-3(d), illustrates a timing charts indicating the waveforms of synchronizing signals added to an image signal reproduced from a magnetic disk for the purpose of explaining the above-described problem.
FIG. 3(a) is a diagram continuously showing a synchronizing signal added to an image signal reproduced from a magnetic disk, wherein point A indicates a point to start recording. FIG. 3(b) shows a signal delayed by 1/2 H from the signal shown in FIG. 3(a).
Skew compensation is performed by switching the signals shown in FIGS. 3(a) and 3(b) every time the magnetic disk performs a single rotation. FIG. 3(c) shows a waveform when the signal shown in FIG. 3(a) is switched to the signal shown in FIG. 3(b), and FIG. 3(d) shows a waveform when the signal shown in FIG. 3(b) is switched to the signal shown in FIG. 3(a).
As shown in FIGS. 3(c) and 3(d), extra pulses as shown by points B and C are produced when skew compensation is performed, and the continuity of the horizontal synchronizing signal is not maintained at these points in the prior art.
Furthermore, in the conventional apparatus, when the track to be reproduced is changed from an unrecorded track to a recorded track, or from a track on which an image signal corresponding to an odd-numbered field is recorded to a track on which an image signal corresponding to an even-numbered field is recorded (or vice versa), discontinuity of the horizontal synchronizing signal occurs in the reproduced still-picture image signal. For example, when the reproduced still-picture image signal is supplied to an external apparatus, such as a monitoring apparatus or the like, the external apparatus operates in accordance with the synchronizing signal added to the supplied still-picture image signal. Since the added horizontal synchronizing signal is discontinuous, there is the possibility that the picture frame made from the supplied still-picture image will be disturbed.
Moreover, since the composite synchronizing signal added to the reproduced image signal is reproduced from the magnetic disk, there is the possibility that a part of the composite synchronizing signal will be missing due to dropouts caused by the adherence of dust, scratches and the like, or that the signal will be deteriorated due to the penetration of noise from the outside, uneven rotation of the magnetic disk and the like.
In the prior art, when an image signal reproduced from a magnetic disk by the above-described still video reproducing apparatus is displayed as a still picture using, for example, a monitoring apparatus, it is possible to display a stable still picture even if the composite synchronizing signal added to the reproduced image signal is deteriorated as described above, because an AFC (automatic frequency control) circuit is provided in the monitoring apparatus. However, when a reproduced image signal to which a deteriorated composite synchronizing signal has been added is input to an image input apparatus (for example, an image memory apparatus or the like) not having the AFC circuit, various kinds of synchronizing signals formed according to the deteriorated composite synchronizing signal also become incorrect. As a result, the reproduced still-picture image signal processed according to the incorrect synchronizing signals is also deteriorated. Hence, the input of a normal image signal was not performed in some cases.

Image signal reproducing apparatus having a synchronizing signal generator


The radiation image reading apparatus includes a reading device of a radiation image recorded in a radiation recording medium, a dose detecting device which detects a dose of radiation applied to record the radiation image, and a computing device by which linearity in radiation image reading is calculated using a plurality of radiation images with varying doses of radiation that have been read, and using detected doses of radiation applied to record the respective radiation images. The radiation image reading method is executed in the apparatus. The apparatus and method can check its linearity by a simple procedure and can adjust the linearity in accordance with the result of checking. The apparatus and method enable consistent outputting of satisfactory diagnostic images with the appropriate contrast. Therefore, the apparatus and method are suitable for use with a radiation imaging system typically using a phosphor sheet.

This invention relates to the field of technology in the apparatus and the method for reading radiation images that are typically used in diagnostic radiology. More particularly, the invention relates to an apparatus and a method for reading radiation images that are adapted for detection of the linearity in image reading by a simple procedure.
A system for diagnostic radiology using a stimulable phosphor has been commercialized as exemplified by CR (Computed Radiography) such as FCR (Fuji Computed Radiography manufactured by Fuji Photo Film Co., Ltd.). When illuminated with a radiation (e.g. X-rays, xcex1-rays, xcex2-rays, xcex3-rays, electron beams or ultraviolet rays), a stimulable phosphor accumulates a portion of the radiation energy and, upon subsequent illumination with exciting light such as visible light, the phosphor produces stimulated light emission in accordance with the accumulated energy.
In a system for diagnostic radiology using the stimulable phosphor, the radiation image of a subject such as the human body is radiographed and recorded in a sheet having a stimulable phosphor layer (hereunder referred to as a xe2x80x9cphosphor sheetxe2x80x9d), which is scanned two-dimensionally with exciting light to emit stimulated light which, in turn, is read photoelectrically to produce a picture signal on the basis of which the radiation image of the subject is output as a visible image on a photographic material such as a radiographic film or a display device such as a CRT (see, for example, U.S. Pat. No. 4,258,264 and Unexamined Published Japanese Patent Application (kokai) No. 11395/1981).
The system using a stimulable phosphor has many advantages and its current use in the area of medical diagnosis is well anticipated to extend to non-medical fields such as the detection of flaws or cracks in industrial products. For example, the transmitted radiation image of round bars and steel pipes may be reproduced in the manner just described above. Since a damaged area absorbs less radiation than the sound area, it comes out darker than the surrounding area of the reproduced image, thus enabling the detection of the flaw or crack that cannot be seen from the outside.
To perform correct diagnosis and detection by means of the radiation imaging system, the subject radiographed and recorded in the phosphor sheet must be reproduced to give the correct image. In the radiation imaging system, the signal obtained by reading the radiation image usually receives processing such as A/D conversion and log conversion to produce digital image data for the radiographed and recorded radiation image. To reproduce the correct image, the image reading apparatus must maintain the intended linearity. In other words, the dose of radiation to which the radiation recording medium such as the phosphor sheet has been exposed during radiation imaging (which is hereunder sometimes referred to as the xe2x80x9cexposed dosexe2x80x9d) must have a linear (1:1) correspondence with the image data obtained by the image reading process.
The linearity of the image reading apparatus is one of the important characteristics for ensuring that the image that has been read is correctly reproduced as a visible image. If the linearity changes, inconveniences occur as exemplified by the change in the contrast of the reproduced image and this leads to an error in diagnosis by a system for diagnostic radiology.
It is therefore a first object of the present invention to provide a radiation image reading apparatus that is suitable for use with a radiation imaging system typically using a phosphor sheet, that is capable of checking for linearity by a simple procedure, with an optional capability of linearity adjustment in accordance with the result of checking, and which enables consistent outputting of diagnostic images with appropriate contrast.
A second object of the present invention is to provide a radiation image reading method that is executed simply and easily in the above described radiation image reading apparatus.
This first object of the invention can be attained by a radiation image reading apparatus comprising a reading device of a radiation image recorded in a radiation recording medium, a dose detecting device which detects a dose of radiation applied to record the radiation image in the radiation recording medium and a computing device by which linearity in radiation image reading is calculated using a plurality of radiation images with varying doses of radiation that have been read by the reading device, as well as the doses of radiation applied to record the respective radiation images and which have been detected by the dose detecting device.
Preferably, the radiation recording medium has the plurality of radiation images with varying the doses of radiation recorded therein by split recording. In another preferred embodiment, the radiation recording medium has the plurality of radiation images with varying the doses of radiation recorded therein using at least one filter having a known radiation transmittance. Preferably, the at least one filter is a radiation filter in a form of a step wedge that transmits a radiation. Preferably, the radiation filter in the form of the step wedge transmits the radiation by varying degrees of 50%, 20% and 5%.
In yet another preferred embodiment, the apparatus further comprises a correction device that corrects for the linearity in accordance with a result of the linearity calculation by the computing device.
Preferably, a difference between the dose of radiation in the plurality of the radiation images is in a range of from 1:3 to 1:1000 in terms of a ratio. Preferably, when image data of the radiation image is antilogarithm data reverted to a linear state, the linearity is expressed as a ratio in the image data divided a ratio in exposed dose and if the calculated linearity is outside a range of from 0.8 to 1.2 the correction device corrects for the linearity.
Preferably, when image data Q0 and Q1 of the radiation images are log converted density data having a 4-digit dynamic range assigned to 10 bits and are read from the radiation images recorded by applying the doses X0 and X1 of radiation, respectively, the linearity is expressed by a following equation and if the calculated linearity is outside a range of from 0.8 to 1.2 the correction device corrects for the linearity.
the linearity={(Q1xe2x88x92Q0)/256}/log(X1/X0)
Preferably, the dose detecting device is a dosimeter for measuring the dose of radiation applied to record the radiation image. Preferably, the radiation recording medium is a stimulable phosphor sheet.
The second object of the invention can be attained by a radiation image reading method comprising the steps of detecting doses of radiation applied to record the respective radiation images in at least one radiation recording medium by varying the doses of radiation, reading the radiation images recorded in the at least one radiation recording medium and calculating linearity in radiation image reading using a plurality of radiation images with varying the doses of radiation that have been read, as well as the doses of radiation applied to record the respective radiation images and which have been detected.
Preferably, the plurality of radiation images are recorded in the at least one radiation recording medium by split recording. Preferably, the plurality of radiation images are recorded in the at least one radiation recording medium using at least one filter having a known radiation transmittance.
In the preferred embodiment, the method further comprises the steps of correcting for the linearity in accordance with a result of the linearity calculation by the computing device. Preferably, a difference between the dose of radiation in the plurality of the radiation images is in a range of from 1:3 to 1:1000 in terms of a ratio. Preferably, when image data of the radiation image is antilogarithm data reverted to a linear state, the linearity is expressed as a ratio in the image data divided a ratio in exposed dose and if the calculated linearity is outside a range of from 0.8 to 1.2 the linearity is corrected.
Preferably, when image data Q0 and Q1 of the radiation images are log converted density data having a 4-digit dynamic range assigned to 10 bits and are read from the radiation images recorded by applying the doses X0 and X1 of radiation, respectively, the linearity is expressed by a following equation and if the calculated linearity is outside a range of from 0.8 to 1.2 the linearity is corrected.
the linearity={(Q1xe2x88x92Q0)/256}/log(X1/X0)
Preferably, the doses of radiation applied to record the radiation images are measured by a dosimeter. Preferably, the at least one radiation recording medium is a stimulable phosphor sheet.

Apparatus and method for reading radiation images


Embedded Media Markers (EMM) are optical-filter-like overlaid marks that can be printed on a part of a paper document that signify the existence of media associated with that part of the document. Users take a picture of an EMM-signified document patch using a cell phone camera, and the media associated with the EMM-signified document location is retrieved and displayed on the phone. Unlike bar codes, EMMs are nearly transparent and thus do not interfere with the document contents. Retrieval of media associated with an EMM is based on image local features of the captured EMM-signified document patch. A semi-automatically technique places an EMM at a location in a document, in such a way that the EMM encompasses sufficient identification features with minimal disturbance to the original document.

1. Field of the Invention
This invention relates in general to embedded media markers, which signify the existence of media associated with a part of a document containing the embedded media marker, and also to methods and systems for generating an article including aforesaid embedded media markers.
2. Description of the Related Art
Although paper is one of the most widely used devices for viewing information, it cannot play dynamic media such as video and audio. On the other hand, cell phones are increasingly used to play audio and video but cannot match paper's high resolution, large display size, flexibility in spatial organization, outdoor-readability and robustness for static content. It is now possible to combine the two, using image recognition technology to link paper documents to corresponding dynamic media. A cell phone camera is used to capture an image of a document patch. The document patch is identified using features in the image, and digital media linked to that location in the document is retrieved and then played on the cell phone.
A common method for creating this type of media link on a paper document is to print coded markers on the document. Examples of such markers include two-dimensional bar codes and printed patterns of dots, described in Hecht, B., M. Rohs, J. Schöning, and A. Krüger, Wikeye—Using Magic Lenses to Explore Georeferenced Wikipedia Content, Proceedings of the 3rd International Workshop on Pervasive Mobile Interaction Devices (PERMID), pp 6-10, both of which are well known to persons of skill in the art. However, these markers are visually obtrusive and interfere with the document content layout. DataGlyphs, described in Hecht D. L., Embedded Data Glyph Technology for Hardcopy Digital Documents, SPIE—Color Hard Copy and Graphics Arts III, Vol. 2171. February 1994, pp 341-352, overcome these problems by printing a nearly invisible machine-recognizable pattern on the paper. However, this type of marker requires high resolution printers and cameras to identify document locations. Electronic markers such as RFID, described, for example, in Reilly, D., M. Rodgers, R. Argue, et al., Marked-up maps: combining paper maps and electronic information resources, Personal and Ubiquitous Computing, 2006, 10(4): pp 215-226, can also be used, but result in substantial increase of production costs.
Other systems use features of the document content itself for identifying the relevant document patch and using it to create a media link. For example, HotPaper, described in Erol, B., Emilio Antunez, and J. J. Hull, HOTPAPER: multimedia interaction with paper using mobile phones, Proceedings of Multimedia '08, pp 399-408, and Mobile Retriever, described in Liu, X. and D. Doermann, Mobile Retriever: access to digital documents from their physical source, Int. J. Doc. Anal. Recognit., 2008. 11(1): pp 19-27, use features based on document text such as the spatial layout of words. Other systems such Bookmarkr, described in Henze, N. and S. Boll, Snap and share your photobooks, Proceedings of Multimedia '08, pp 409-418, and MapSnapper, described in Hare, J., P. Lewis, L. Gordon, and G. Hart, MapSnapper: Engineering an Efficient Algorithm for Matching Images of Maps from Mobile Phones, Proceedings of the SPIE, Volume 6820, pp 68200L-68200L-11 (2008), use pixel level image features, such as the SIFT algorithm, described in Lowe, D. G., Distinctive Image Features from Scale-Invariant Keypoints, Int. J. Comput. Vision, 2004, 60(2): pp 91-110, to recognize generic document content such as pictures and graphic elements. With these systems, visually obtrusive marks are not required for identification.
However, both the conventional marker-based methods and content-based methods lack media type indicators. Although bar codes and Data Glyphs are visible, they do not directly indicate the existence or type of media associated with them. When content-based feature are used, there is no on-paper indication to the user that there is media linked to the document. As a result, a user of the aforesaid HotPaper has to pan a camera phone over the paper document to look for hotspots until a feedback such as a red dot or vibration is presented on the cell phone.
Many systems, including HotPaper, Bookmarkr, Mobile Retriever, CAM, described in Parikh, T. S., P. Javid, S. K., K. Ghosh, and K. Toyama, Mobile phones and paper documents: evaluating a new approach for capturing microfinance data in rural India, Proceedings of CHI'06, pp. 551-560, have been proposed for using a camera phone to capture and recognize images of paper documents, and then access the linked digital media. For example, Rohs proposed a system, described in Rohs, M., Real-world interaction with camera-phones, Proceedings of UCS. IPSJ Press (2004), for augmenting real time images of a paper map with dynamic weather information for specific geographical areas. The aforesaid HotPaper enables users, with a camera phone as a Magic Lens, to add and play multimedia annotations linked to text patches in paper documents. The aforesaid Bookmarkr facilitates retrieval and sharing of digital photos with snapshots of printed photos.
Marker-based systems like the one proposed by Rohs as well as CAM depend on 2D barcodes to identify and manipulate the document contents. On the other hand, WikEye, described in Hecht, B., M. Rohs, J. Schöning, and A. Krüger, Wikeye—Using Magic Lenses to Explore Georeferenced Wikipedia Content, Proceedings of the 3rd International Workshop on Pervasive Mobile Interaction Devices (PERMID), pp. 6-10, adopts black dots arranged in a grid as markers. Although easy to detect, the barcodes and dots are often visually obtrusive, require changing the format of original documents, and occupy extra display space on paper. Recent Designable Marker, described in Reilly, D., M. Rodgers, R. Argue, et al., Marked-up maps: combining paper maps and electronic information resources, Personal and Ubiquitous Computing, 2006. 10(4): p. 215-226, improves 2D barcodes by incorporating human-readable components into the mark design, but does not address the issues of document-altering and wasted paper space. To overcome these problems, Data Glyphs and Anoto patterns, well known to persons of skill in the art, were proposed. However, these encoding patterns have to be printed by high resolution printers and captured by specialized cameras for decoding. Moreover, Fujitsu proposed a steganographic printing technique that embeds invisible bar codes into printed color images. All of these visible/invisible barcodes, Data Glyphs and Anoto patterns do not reveal to the human meaningful information about the available media.
To avoid some limitations of marker-based systems, PBAR, described in Hull, J. J., B. Erol, J. Graham, Q. Ke, H. Kishi, J. Moraleda, and D. G. V. Olst, Paper-based Augmented Reality, Proceedings of Int. Conf. on Artificial Reality and Telexistence, pp. 205-209, HotPaper, Mobile Retriever and LLAH, described in Nakia, T., K. Kise, and M. Iwamura, Use of affine invariants in locally likely arrangement hashing for camera-based document image retrieval, Proceedings of 7th Int'l Workshop DAS'06, pp. 541-552, use text features, e.g. the spatial layout of words in a text chunk, to identify document patch images. Bookmarkr, MapSnapper, and FIT, described in Liu, Q., H. Yano, D. Kimber, C. Liao, and L. Wilcox, High Accuracy and Language Independent Document Retrieval With A Fast Invariant Transform, Proceedings of ICME'09, pp 386-389, adopt pixel level image features to recognize generic contents including text, pictures and graphic elements. With these systems, visually obtrusive barcodes are not required for identification, the original document formats are intact, and document publishers do not need extra space for barcode printing. On the other hand, since these systems completely remove visible markers on document pages, there is no indication to the user that multimedia information is available at certain locations in the document. Moreover, none of these approaches have marks that can guide users' captures for document patch identification.
Accordingly, new non-obstructive embedded media markers, which can be generated using not only high resolution printing devices but also low-resolution printing devices and methods for implementing and using those markers are needed.

Embedded media markers and systems and methods for generating and using them