Apparatus and method for eliminating cross conduction of self-driven synchronous rectifiers in power converters caused by non-idealized ringing of parasitic capacitances and inductors. In an exemplary embodiment, the apparatus includes synchronous rectifiers or some hybrid topology having at least one synchronous rectifier coupled to a damping circuit having at least one switching device. The switching device is activated (ON) at a time when at least one of the synchronous rectifiers is supposed to remain inactive (OFF). Accordingly, when the switching device is ON, the device effectively dampens any ringing present at the synchronous rectifier that may cause the rectifier to inappropriately transition ON. The damping circuit of the present invention utilizes the same signals present to control the synchronous rectifier(s) and requires no additional control circuitry. Additionally, the damping circuit dramatically improves the efficiency of self synchronous power converters and is topology independent.

Power converters that employ self-driven synchronous rectifiers are becoming increasingly popular in the power industry today, because of their compact size and high efficiency. For instance, one particular class of self-driven synchronous rectifier circuits employing active clamp topologies may attain conversion efficiencies exceeding 90%, (e.g., a 48 V to 5 V DC-to-DC converter).
Nevertheless, the efficiency of self-driven synchronous rectifiers, are often substantially reduced by non-idealized parasitic elements, such as: (1) stray inductances introduced by component interconnections, (2) transformer leakage inductances, (3) body capacitances of the synchronous rectifiers, (4) and other related parasitic phenomena. Such parasitic elements form high frequency resonant circuits which can oscillate (generating a "ringing") as the synchronous rectifier gates transition between ON-and-OFF and OFF-and-ON. As result, during transition periods, the ringing creates a momentary short circuit of the synchronous rectifiers, allowing the synchronous rectifier to simultaneously "cross conduct" for brief periods of time. Such simultaneous conduction (i.e., cross conduction) can be a significant source of power loss and inefficiency for self-driven synchronous rectifiers.
Cross conduction and ringing is becoming more troublesome as power converter designs migrate to very low output voltages (e.g., 1.5 V to 2 V). Low output voltage converters often require the use of low-threshold-voltage type Metal Oxide Silicon Field Effect Transistors (MOSFETs) (typically less than <2.5 volts), because voltages available at the winding terminals of such transformers are no longer sufficient to adequately drive traditional power MOSFETs, (e.g., 10 volt gate drive). Unfortunately, low threshold MOSFETs are considerably more susceptible to cross conduction than conventional 10 volt drive power MOSFETs.
What is needed, therefore, is way to substantially eliminate cross conduction of rectifiers in self-driven synchronous converters without introducing unnecessary circuit complexity or additional parasitic loss mechanisms.

Method and apparatus for damping ringing in self-driven synchronous rectifiers


A memory device driving circuit is disclosed which drives a memory device including a first electrode, a second electrode, and a memory layer interposed between the first electrode and the second electrode. The memory device driving circuit may include a main driver connected to the memory device, to drive the memory device, and a secondary driver connected between the memory device and the main driver, to control a set resistance of the memory device. The memory device driving circuit may freely adjust the set resistance of the memory device, to maintain the resistance of the memory device at a desired value. Accordingly, an improvement in the operation reliability of the memory device may be achieved.

1. Field
Example embodiments relate to a memory device driving circuit for driving a resistive memory device capable of having two or more states in accordance with a variation in resistance and a method of fabricating the same. Other example embodiments relate to a memory device driving circuit which may include a secondary driver connected to a memory device including a memory layer arranged between a first electrode and a second electrode, to control a set resistance of the memory device and a method of fabricating the same.
2. Description of the Related Art
In accordance with recent development of data compression and transmission techniques, development of new electronic appliances (e.g., portable terminals, various smart cards, electronic cash, digital cameras, memories for games, MP3 players and/or multimedia players) has increased. Such new electronic appliances may be configured to use an increased amount of information. The demand for various memory devices capable of storing an increased amount of data may have also been increased. Increased use of portable information appliances may have increased the demand for a memory device having non-volatile characteristics preventing or reducing recorded information from being erased even in a power-off state. Most memory devices may include a bistable element which is switchable between a higher resistance state and a lower resistance state upon receiving a voltage. Resistive memory devices, which have a concept compared to capacitive memory devices, may include a memory that varies in resistance in accordance with a voltage applied thereto, and may store data corresponding to the resistance variation.
Chalcogenide materials, semiconductor, and various oxides and nitrides may have resistive memory properties. Organic materials may have resistive memory properties. Resistive memory devices may have drawbacks of increased driving voltage and current, decreased durability and decreased thin film handling properties. Because such drawbacks have been overcome in accordance with recent developments of material engineering, resistive memory devices may be currently non-volatile, lower-power, higher-density, and multi-bit operating memories. Examples of such a resistive memory device may include a phase change RAM, an organic memory, an oxide resistive RAM (OxRAM) and/or a metal filament memory.
The resistive memory device will be described in conjunction with, for example, the organic memory. The organic memory may include an organic memory layer between an upper electrode and a lower electrode. Memory cells providing bistability characteristics may be formed at points where the upper and lower electrodes cross each other.
The memory cells of the resistive memory device may have two states, namely, a set state corresponding to a lower resistance state and a reset state corresponding to a higher resistance state. When it is assumed that data of "1" corresponds to the lower resistance state, and data of "0" corresponds to the higher resistance state, two logic states of data may be stored.
In such a memory device, read-out of data may be carried out as follows. One bit line and one word line may be selected from a memory matrix, to select a specific memory cell. Thereafter, current may be supplied from the outside of the memory device to the specific memory cell. A voltage variation may occur in the memory cell in accordance with the resistance state of the organic memory layer in the memory cell. In accordance with the voltage variation, data of "0" or "1" may be read out.
In most memory devices, however, an accurate read out of the voltage variation may be difficult unless a separate amplifier is used, because the resistance in the set state may be relatively small. The configuration of such a memory device may become complex. The resistance in the set state may be non-uniform. Errors may be generated during the operation of the memory device for reading the memory cell.


In one example, receiver circuitry for a communication system comprises signal processing circuitry configured to receive a data signal and generate a processed data signal, and error slicer circuitry. The error slicer circuitry is coupled to the output of the signal processing circuitry, and configured to receive the processed data signal. The error slicer circuitry comprises a first error slicer configured to receive a clock signal, and output a first error signal based on a first state of the clock signal and processed data signal. The first error slicer is further configured to output a second error signal based on a second state of the clock signal and the processed data signal.

Receiver circuitry of a pulse amplitude modulation 4-level (PAM4) receiver uses three data slicers per clock phase to detect the four data levels (e.g., 00, 01, 10, and 11). Each of the data slicers corresponds to a respective one of a DH (a high data latch voltage) threshold, DZ (a middle data latch voltage) threshold, and DL (a low data latch voltage) threshold. Accordingly, for four clock phases, the receiver circuitry includes twelve data slicers. Further, for offset cancellation and data threshold level adaptions within the receiver circuitry, the receiver circuitry includes one error slicer per clock phase. For each clock phase, a first error slicer detects a voltage level EHP (a positive error latch voltage with a high voltage magnitude), a second error slicer detects a voltage level ELP (a positive error latch voltage with a low voltage magnitude), a third error slicer detects a voltage level EHN (a negative error latch voltage with a high voltage magnitude), and a fourth error slicer detects a voltage level ELN (a negative error latch voltage with a low voltage magnitude). Accordingly, for four clock phases, the receiver circuitry includes four error slicers. In total, a receiver circuitry that uses four clock phases has 16 total slicers (e.g., 12 data slicers and 4 error slicers). The large number of error and data slicers increases the overall circuit size of the receiver circuitry and power used by the receiver circuitry. Further, the large number of error and data slicers increases the loading to signal processing circuitry of the receiver circuitry, limiting the bandwidth of the signal processing circuitry.

Reduced power and area efficient receiver circuitry


There are provided melt extruded blends of diene based rubber and preextruded polyphenylene ether, or blends thereof with an effective amount of a stabilizer such as a hindered phenol or metal deactivator/hindered phenol. The resulting polyphenylene ether composition can be further extruded with a polymeric organic matrix material, such as a polyamide or polyetherimide. When molded, the polyphenylene ether compositions have been found to resist loss of impact strength upon thermal aging and recycling.

The present invention relates to blends comprising polyphenylene ether and diene based rubber which exhibit improved resistance to loss of impact strength when the blends have been molded and thereafter thermally recycled. More particularly, the present invention relates to blends of diene based rubber and polyphenylene ether, where the polyphenylene ether used in the blend has been previously extruded, prior to melt extrusion with the diene based rubber.
Prior to the present invention, antioxidants, such as hindered phenols, were often used as stabilizers for polyphenylene ethers, while metal deactivators/antioxidants were frequently employed to reduce metal catalyzed degradation in unsaturated rubber. Commercially available stabilizers have been used with butadiene copolymers, such as Kraton KD1102 manufactured by Shell Chemical Company, which is a styrene-butadiene-styrene (SBS) block copolymer. Antioxidants also have been found to minimize crosslinking of diene based rubber resulting from oxidation during high temperature processing. In the event of excessive crosslinking prior to or during molding, diene based rubber can become ineffective as an impact modifier for thermoplastics, such as polyphenylene ether.
Although metal deactivators and/or antioxidants have been found effective for stabilizing diene based rubber, experience has shown that blends of such stabilized diene based rubber and polyphenylene ether which have been molded, often experience a reduction in toughness when thermally recycled, as compared to the blend when initially molded. One possible explanation is that crosslinking occurs in the diene blocks of the impact modifier during the subsequent melt extrusion steps of the recycled thermoplastic, and the toughness of the molded thermoplastic is reduced. Metal residues such as copper in the polyphenylene ether also can catalyze the crosslinking of the unsaturated rubber. Accordingly, in order to maintain the impact properties of molded blends of polyphenylene ether and diene based rubber subject to recycling, additional methods to improve the thermal stability of the diene based rubber subject to recycling are constantly being sought.

Thermally stable blends of polyphenylene ether, diene based rubber and an antioxidant/metal deactivator


An automobile covering device includes a hollow cylindrical member having two closed ends, an axial slot and a water outlet. A U-shaped handle has two ends connected pivotally to the two closed ends of the cylindrical member. A cylinder with an axial shaft is received coaxially and rotatably in the cylindrical member. The axial shaft has two free ends which pass through the two closed ends of the cylindrical member, respectively. Two spiral torsional springs are respectively mounted on the two closed ends of the cylindrical member. Each of the spiral torsional springs has a first end connected to one of the free ends of the axial shaft and a second end connected to one of the closed ends of the cylindrical member. A roll of cover cloth is wound on the cylinder and has a pull end passing through the axial slot of the cylindrical member. Two rollers are rotatably mounted on the two closed ends of the cylindrical member, respectively. A fastening device is provided for fastening the pull end of the cover cloth and the cylindrical member on an automobile.

1. Field of the Invention
This invention relates to an automobile covering device, more particularly to an automobile covering device in which a cover cloth can be easily applied to the automobile.
2. Description of the Related Art
FIG. 1 shows a conventional automobile covering device which includes a base frame (A) having an automatically winding device (B) mounted rotatably therein. The automatically winding device (B) has a roll of cover cloth (D) wound thereon. A fastening device (C) includes a rope member, two hooks (C2) provided on the base frame (A) and a hook rod (C3) provided on a pull end of the cover cloth (D). In use, the rope member is tied on the trunk lid of the automobile, as illustrated in FIG. 2A. The rope member and the hooks (C2) are hooked on the rear bottom of the automobile, as illustrated in FIG. 2B. The cover cloth (D) is then pulled over the automobile from the rear to the front of the automobile in order to cover the automobile, as illustrated in FIGS. 2C and 2D. However, when the cover cloth (D) is pulled over the automobile, a great friction force between the cover cloth (D) and the external surface of the automobile is produced. Therefore, pulling the cover cloth is a relatively strenuous work. In addition, the paint on the external surface of the automobile is liable to be damaged when a user drags the cover cloth (D) in order to overcome said friction force.


In a CMOS semiconductor device, a pMOS transistor and an nMOS transistor are formed on a single substrate. Each of the source/drain regions of the nMOS transistor and the pMOS transistor has LDD structure composed of a combination of a low concentration impurity region and a high concentration impurity region. The low concentration impurity region of the LDD structure of the pMOS transistor is formed in a self-align manner by ion implantation using a sidewall spacer with relatively thick film thickness. The low concentration impurity region of the LDD structure of the nMOS transistor is formed in a self-align manner by ion implantation using a relatively thin sidewall spacer as a mask. The sidewall spacer with thick film thickness of the pMOS transistor restrains that the channel between the source/drain regions is shortened due to thermal diffusion to cause punch through. As for the sidewall spacer of the nMOS transistor, its film thickness is selected to effectively restrain hot carrier effect in the vicinity of the drain and restrain degradation of current handling capability due to parasitic resistance to the minimum.

1. Field of the Invention
The present invention relates to a MIS device, and particularly to an improvement of so-called LDD (Lightly Doped Drain) structure of a PMOS transistor and a NMOS transistor formed on the same substrate and a method of manufacturing the improved LDD structure.
2. Description of the Background Art
A device provided with multi-layered structure of metal-insulator-semiconductor is generally referred to as an MIS device. An MOS device is a kind of MIS device, in which an oxide film is used for an insulator of the MIS device.
Semiconductor devices in which a p-channel MOS field effect transistor (referred to as a pMOS transistor hereinafter) and a n-channel MOS field effect transistor (referred to as a NMOS transistor hereinafter) are formed on a single semiconductor substrate include a CMOS semiconductor device, for example. FIG. 6 is a sectional structure view of a conventional CMOS semiconductor device. A p well region 8a and a n well region 8b in contact with each other are formed on a surface of a silicon substrate 6. Thick field oxide films 7 are formed at given positions on the main surface of the silicon substrate 6. The p well region 8a surface surrounded by the field oxide film 7 forms a n MOS transistor forming region, and the n well region 8b surface surrounded by the field oxide film 7 forms a pMOS transistor forming region.
The nMOS transistor 20 has a gate electrode 1a on the surface of the p well region 8a with a thin gate insulating film 9 disposed therebetween. Sidewall spacers 3a and 3a composed of insulating films are formed on sidewalls of the gate electrode 1a. Also, a pair of source/drain regions including n.sup.- impurity regions 2a, 2a of relatively low concentration and n.sup.+ impurity regions 5a, 5a of relatively high concentration are formed in the p well region 8a surface. Such structure of source/drain regions is referred to as LDD structure. Source/drain interconnection layers 11, 11 are respectively connected to the surfaces of the n.sup.+ impurity regions 5a, 5a of the source/drain region.
Also, the pMOS transistor 30 includes a gate electrode 1b on the surface of the n well region 8b with a thin gate insulating film 9 disposed therebetween. Sidewall spacers 3b, 3b formed of insulating films are formed on the sidewalls of the gate electrode 1b. Furthermore, source/drain region composed of p.sup.- impurity regions 2b, 2b of relatively low concentration and p.sup.+ impurity regions 5b, 5b of relatively high concentration are formed at the surface of the n well region 8b. This source/drain region forms the so-called LDD structure. Moreover, source/drain interconnection layers 11, 11 are respectively connected to the p.sup.+ impurity regions 5b, 5b of the source/drain region. The silicon substrate 6 surface in which a transistor is formed is covered with a thick interlayer insulating layer 10.
Next, a method of manufacturing the above-described CMOS semiconductor device will be described referring to FIGS. 7A-7H.
First, referring to FIG. 7A, a p well region 8a and an n well region 8b are formed on a silicon substrate 6 surface, and thick field oxide films 7 are formed at given regions on the silicon substrate 6 surface. Furthermore, gate insulating films 9 are formed on the surfaces of the p well region 8a and the n well region 8b. A polysilicon layer 12 is deposited on the surface of the gate insulating film 9.
Next, referring to FIG. 7B, the polysilicon layer 12 is patterned into a rectangular form using the photolithography method and the anisotropic etching method to form the gate electrode 1a of the nMOS transistor and the gate electrode 1b of the pMOS transistor.
Moreover, referring to FIG. 7C, after covering the surface of the p well region 8a with a resist pattern 4a, p type impurity ions 15 such as boron (B) are implanted into the n well region 8b using the gate electrode 1b as a mask. By this ion implantation, p.sup.- impurity regions 2b, 2b of low concentration are formed on the n well region 8b surface.
Furthermore, as shown in FIG. 7D, after removing the resist pattern 4a on the p well region 8a surface, a resist pattern 4b is now formed covering the surface of the n well region 8b. Subsequently, n type impurity ions 16 such as phosphorus (P) or arsenic (As) are directed on the p well region 8a surface using the gate electrode 1a as a mask to form n.sup.- impurity regions 2a, 2a of low concentration.
Furthermore, as shown in FIG. 7E, after removing the resist pattern 4b, an oxide film 13 is deposited all over the surface of the silicon substrate 6 using the low pressure CVD (Chemical Vapor Deposition) method.
Subsequently, referring to FIG. 7F, the oxide film 13 is anisotropically etched to form sidewall spacers 3a, 3b having the same film thickness on the sidewalls of the gate electrodes 1a and 1b.
Next, referring to FIG. 7G, after forming a resist pattern 4c covering the surface of the n well region 8b again, n type impurity ions 17 such as arsenic are implanted using the gate electrode 1a and the sidewall spacers 3a as masks. Subsequently, after removing the resist pattern 4c, thermal treatment is applied for activating the implanted ions. Thus, n.sup.+ impurity regions 5a, 5a of high concentration are formed in the p well region 8a surface. The LDD structure of the source/drain region of a nMOS transistor is then completed.
Furthermore, referring to FIG. 7H, a new resist pattern 4d is formed covering the surface of the p well region 8a. P type impurity ions 18 are directed on the n well region 8b surface using the gate electrode 1b and the sidewall spacers 3b as masks. Next, after removing the resist pattern 4d, applying thermal treatment, the ions implanted into the n well region 8b are activated. In this way, the p.sup.+ impurity regions 5b, 5b are formed. Thus, the LDD structure of source/drain region of a pMOS transistor is completed in the above steps.
Subsequently, an interlayer insulating film 10 is formed on the surface of the silicon substrate 6, and a contact hole is formed at a given position. An interconnection layer 11 is then formed at a given position through the contact hole to finish the process of manufacturing a CMOS semiconductor device (not shown).
The progress of fine processing technique of element structure is pointed out as technical background of a CMOS semiconductor device with such LDD structure as described above. The tendency of element structure miniaturization is seen in the aspects such as shortening of the gate length according to the scale down rule and forming of shallow junction region in a MOS transistor. The "scale down rule" is described in VLSI Electronics Microstructure Science, Volume 18, "Advanced MOS Device Physics", Academic Press. Inc. 1989. Also, it means shortening of the gate length of a MOS transistor, that is, shortening of a channel, which causes various problems so-called short channel effect. That is to say, for example, hot carriers are generated due to the high electric field produced in the vicinity of a drain in a short channel MOS transistor, and a portion of the hot carriers are captured in a trap in the gate insulating film to form a new level. As a result, characteristic degradation such as shift of a threshold value voltage of a MOS transistor and a decrease of mutual transconductance are caused. The high electric field produced in the vicinity of a drain also caused degradation of the drain breakdown voltage due to the avalanche breakdown. The LDD structure of a MOS transistor is a device proposed to solve such problems. Especially, it restrains generation of the high electric field by forming an impurity region with moderately changing concentration distribution in the vicinity of the drain to obtain high avalanche breakdown voltage and a decrease of reliability degradation due to hot carriers.
In a miniaturization method of CMOS semiconductor devices, it is needed to reduce the gate length L.sub.Gp of pMOS transistor 30 and the gate length L.sub.Gn of nMOS transistor 20 and make the lengths equal. As the gate lengths L.sub.Gp, L.sub.Gn of pMOS transistor 30 and nMOS transistor 20 get longer, the gate capacitance increases to increase the RC constant, with the result that operation of transistors are delayed. Accordingly, the channel lengths Ln and Lp defined in a self aligning manner utilizing gate electrodes 1b and 1a are also preferably reduced to have the equal lengths.
However, turning to FIG. 6 again, the pMOS transistor 30 and the nMOS transistor 20 are provided with low concentration impurity regions 2a, 2b of the LDD structure having different shapes in a CMOS semiconductor device manufactured through the manufacturing steps described-above. That is to say, in the pMOS transistor 30, the diffusion length of the low concentration p.sup.- impurity region 2b is extremely small as compared to that of the nMOS transistor 20. Also, the channel length L.sub.p between the high concentration p.sup.+ impurity regions 5b, 5b are shorter than the channel length L.sub.n of the nMOS transistor 20. This is because, boron (B), impurity forming the source/drain region of the pMOS transistor 30, has a larger diffusion coefficient as compared to that of phosphorus and arsenic forming the source/drain region of the nMOS transistor 20. This is understood by comparing the steps shown in the above FIGS. 7G and 7H. In other words, in the nMOS transistor 20, the high concentration n.sup.+ impurity regions 5a, 5a formed in a self-align manner with respect to the sidewall spacers 3a slightly diffuse under the sidewall spacers 3a by the thermal treatment for activation. On the other hand, in the pMOS transistor, the high concentration p.sup.+ impurity regions 5b, 5b formed in a self-align manner with respect to the sidewall spacers 3b widely diffuse under the sidewall spacers 3b in the thermal treatment for activating. In this way, the diffused high concentration p.sup.+ impurity regions 5b, 5b cover the low concentration p.sup.- impurity regions 2b, 2b regions, so that the diffusion length of the low concentration p.sup.- impurity region 2b is decreased. Thus, punch through phenomena easily occurs between the pair of high concentration p.sup.+ impurity regions 5b, 5b narrowed due to diffusion of impurity of large diffusion coefficient. This punch through phenomena is further facilitated as the gate length becomes shorter while the device is refined.
As described above, the LDD structure of the pMOS transistor and the nMOS transistor composed of impurities of different diffusion coefficients are manufactured employing the sidewall spacers 3a, 3b having the same film thickness. Accordingly, if the film thickness of the sidewall spacers 3a, 3b is selected to be suitable for the LDD structure of the nMOS transistor, for example, resistance to the punch through between the high concentration p.sup.+ impurity regions 5b, 5b is easily degraded in a pMOS transistor. On the other hand, if the sidewall spacers are formed with film thickness suitable for the LDD structure of the pMOS transistor, the drain current between the source and the drain is degraded in the nMOS transistor 20. This is because, as the film thickness of the sidewall spacers 3a is increased, the diffusion length of the low concentration n.sup.- impurity regions 2a, 2a is increased, and the low concentration n.sup.- impurity diffusion layers 2a act as parasitic resistance between the source and the drain to degrade the drain current. In this way, in a conventional CMOS semiconductor device, the sidewall spacers 3a, 3b defining the low concentration impurity regions of the LDD structure are formed with the same film thickness in the pMOS transistor and the nMOS transistor, so that a LDD structure which can satisfy requirements of both of the pMOS transistor 30 and the nMOS transistor 20 could not be obtained. Conventionally, by the sacrifice of source-drain current degradation of the nMOS transistor 20 to some extent to prevent the punch through phenomena of the pMOS transistor 30, the film thickness of the sidewall spacers 3a, 3b has been determined focusing on the operational reliability.

MIS device having p channel MOS device and n channel MOS device with LDD structure and manufacturing method thereof


Embodiments of the present invention disclose a method of content-layer based compression of a video being broadcasted over a network. The method may include: receiving a video stream comprising a plurality of video stream frames; identifying in at least some of the plurality of video stream frames at least two content-layers of predefined content-layers to yield corresponding at least two content-layer streams, wherein each of the at least two content-layer streams is associated with one of the at least two content-layers; and compressing each of the at least two content-layer video streams according to predetermined parameters of the content-layer associated with the respective content-layer video stream and according to available resources of the network to yield corresponding at least two compressed content-layer streams.

Generally, an uncompressed video requires a very high data rate. Typically, video data (that typically includes a plurality of still frames) contains abundant amounts of spatial and temporal redundancy. Current video compression methods typically exploit these spatial and temporal redundancy, for example through difference coding. For example, similarities can be encoded by only storing differences between temporally adjacent frames (inter-frame coding) and/or spatially adjacent pixels (intra-frame coding).
Current video compression methods can further employ lossy compression techniques (e.g., quantization) that reduce aspects of the source data that are irrelevant to the human visual perception by exploiting perceptual features of human vision. For example, small differences in color are more difficult to perceive than are changes in brightness. These compression algorithms can average a color across these similar areas to reduce space.

System and method for content-layer based video compression


By concealing the existence of an area using a function (which is referred to as IC privacy function) capable of concealing the data area corresponding to each service (behaving as if the data area does not exist), an existing function provided in the contactless IC card, an access to the data necessary for a service can be inhibited, so as to control to inhibit (lock) use of the contactless IC card on a service-by-service basis.

1. Field of the Invention
The present invention relates to a portable terminal unit having a built-in contactless IC card which deals with a plurality of services, and more particularly a portable terminal unit capable of restricting use of a contactless IC card on a service-by-service basis, using the function capable of concealing the existence of a data area in the contactless IC card on a basis of each service which uses the contactless IC card.
2. Description of the Related Art
A contactless IC card includes an antenna therein, and transmits and receives data using a weak radio wave transmitted from an external terminal. The contactless IC card is appropriate to operation in such an environment as having a lot of vibration and dusts, because of being capable of processing without contacting to a read terminal, as opposed to a contact IC card. Further, because a troublesome work of inserting and detaching the card is not needed, the contactless IC card is adopted worldwide as a prepaid card for a railway, bus, or the like, which requires high-speed processing. Moreover, there are increased cases of use of the contactless IC card being adopted for electronic money, a staff identity card, etc.
Furthermore, in recent years, there has appeared a portable telephone terminal with a mounted contactless IC card, having a railway fare payment function (ticket examination function) and an electronic money function for shopping.
As described above, the contactless IC card can provide a plurality of services (such as the railway fare payment function and the electronic money function, which may be referred to as multiple applications) by a single contactless IC card, and data for each service can be managed in the single card. An individual access right can be set to each data, so as to enable each service to be operated independently.
In the official gazette of the Japanese Unexamined Patent Publication No. Hei-11-120264 (hereafter referred to as Patent document 1), an IC card having respective storage areas for respective uses of electronic money is disclosed. In the official gazette of the Japanese Unexamined Patent Publication No. Hei-9-204484 (hereafter referred to as Patent document 2), in an IC card separately managing electronic money information and purchase point information, there is disclosed a technique for authenticating use of the above information by means of a personal identification number. Also, in the official gazette of the Japanese Unexamined Patent Publication No. Hei-10-340231 (hereafter referred to as Patent document 3), in an IC card capable of handling a plurality of services (functions), there is disclosed a technique for managing data for each service by means of authentication processing of a password, etc.
It is expected that use of portable telephone terminals including mounted contactless IC cards will become more and more popular. Consequently, security measures for the portable telephone terminals in the event of being left behind or stolen will become more important.
In the conventional security measures, when a user inhibits (locks) use of the contactless IC card mounted on the portable telephone terminal, it has been configured to make the contactless IC card unusable by shutting off the external power supply (provided inside the portable telephone terminal) to the contactless IC card. In this case, since the power supply to the contactless IC card is shut off, the entire services (functions) to be provided by the contactless IC card become unusable (an overall lock state).
FIG. 1 shows a diagram illustrating a lock operation in the conventional contactless IC card. A contactless IC card 12 mounted on a portable telephone terminal 10 communicates with portable telephone terminal 10 by wired communication. Portable telephone terminal 10 executes an application "Area 0 generation application" which generates, and refers to, an area 0 in contactless IC card 12, an application "Area 0 viewer" which refers to the area 0, and an application "Area 1 generation application" which generates, and refers to, an area 1. Here, the area 0 and the area 1 are areas for respectively storing data corresponding to different services. The "Area 0 generation application" is an application executing a service using the data stored in the area 0, while the "Area 1 generation application" is an application executing another service using the data stored in the area 1.
An area-0 reader/writer 20 reads and writes data from/to the area 0 in the contactless IC card, and an area-1 reader/writer 22 reads and writes data from/to the area 1 in the contactless IC card. When the contactless IC card is set to a use inhibition (locked) state, the entire services (applications) become unusable because the entire functions in the contactless IC card are suspended due to the shutoff of the power supply, as shown in the figure (the overall lock state).
In order to ensure the security, it is provable that the user ordinarily carries the portable telephone terminal by setting the contactless IC card to the use inhibition state. Here, in the configuration at present, when the contactless IC card is set to the use inhibition state, the entire services become unusable. This produces some inconvenience in usability because even a service not requiring inhibition of use has to be unlocked by means of a lock release operation prior to the use of the relevant service, and has to be locked again by means of a lock operation after the use.
In the aforementioned Patterned document 1, there is a disclosure in regard to inhibition of use (locking) on a basis of each storage area provided for each use. However, in order to afford the lock function, it is necessary to modify the IC card internally. Also, according to the above Patent documents 2 and 3, authentication processing is performed for each service use by the use of a personal identification number (or a password), and the relevant service becomes usable if the authentication is successful, which is not a state of inhibited use of a service. Therefore, the above method is relatively weak as a security measure.


A system for estimating a substance level in a storage unit is disclosed. In one embodiment, the system includes a cable and a control device. The control device sense pulses down the cable and based on the time of reflected pulses determines the level of substance in the storage unit.

Storage units, such as bins, tanks, elevators, are used to hold bulk materials such as grains, woodchips, coal, etc. for storage. It is important to be able to ascertain the correct amount of substance housed in storage units. Having an accurate inventory is essential to the production of goods and therefore to the financial performance of the business.
Obtaining an accurate measurement, however, can be difficult. For example, grain is generally deposited into a grain bin from one location near the top of the container, but for various reasons, the grain inside the grain bins may come to rest in uneven, non-uniform levels. This uneven surface makes it difficult for workers to safely assess accurate volumes.
Manual measurements of grain levels can be dangerous. For example, bins can develop hazardous atmospheres, which can limit the amount of oxygen available for breathing. In addition, grain can clump together from moisture or mold, which creates an empty space beneath the grain as it is removed from the bin. The "bridging" effect that forms from this circumstance can prove to be deadly to a worker who stands on the clumped grain. If the clumped grain collapses into the open area below (the void), a worker standing on the collapsing grain could fall victim to an avalanching effect, which has the potential of burying the worker.
Systems for determining grain levels in grain bins without human interaction have been described in prior art. Single point measurements using technology such as bobs, guided wave radar, open air radar, and ultrasonic have been used to increase the accuracy of grain measurements. Multiple point measurements that implement technology such as 3D level scanners and bob systems are capable of measuring the level of grain at multiple points in the bin. Multiple point measurement systems that can scan the surface of the grain are capable of taking multiple measurements at once to better account for variations in the topography of the grain. Single and multiple point measurement systems, however, require expensive scanning hardware to be mounted to one or more points on each grain bin. The technologies used to measure the grain must be designed to not generate sparks that could ignite flammable suspended particulate matter in the grain bin.
It is thus desirable to provide a system for accurately measuring the amount of substance housed within a storage unit in real time safely, efficiently, and cost effectively.

System for sensing substance levels in a storage unit


An improved method and apparatus for transmitting digital signals in a communications channel by compensating for distortions due to attenuation of high frequency components suffered by the digital signals. In a preferred embodiment, the digital signals are pulses and the compensation is performed at the transmitter without the need for an emphasis driver, by widening the pulses to compensate for the distortion in the channel that results in narrowing of the pulses incurred in the channel. The resulting pulse train is pre-compensated for the distortions caused by the communications channel. The amount of pre-compensation can be determined statically or dynamically.

1. Field of Invention
The present invention relates generally to the field of transmitters in mixed-signal communication channels of the kind used in serial transmissions.
2. Description of Related Art
Signal processing in digital communications is concerned with optimizing performance given the constraints of power, noise, bandwidth limitations, area, memory, sampling limitations and numerous other requirements depending on the architecture employed.
Data communication is moving away from parallel busses and towards serial transmission and serial protocols. System designers are under pressure to reliably send data over low bandwidth channels at rates for which they may not have been optimally designed for, and to pack more communication channels into smaller and smaller spaces. This results in increasingly poorer receive signal levels and higher levels of crosstalk, among other problems. Those who design transmitters for these systems need to find ways of improving the quality of the signals seen by the receiver.
A typical system is shown in FIG. 1. A transmitter 10 sends serial data, typically digital signals in the form of pulses, out through the channel 20, having a channel response transfer function H(s), and is picked up by a receiver 30. The output of the transmitter is a wide bandwidth digital signal. The channel 20 can be a mixed-signal channel utilizing both analog and digital signals. Channel 20, which could be a backplane, a PCB trace, a cable, an optical link, an internet or interchip connection, or any other communications channel, generally has been found to act as a lowpass function filter which filters out the high frequency energy from the transmit signal, as generally the channel is limited in bandwidth. By the time the transmitted signal from the transmitter passes through the communications channel 20 and is received by the receiver, the transmitted signal could be significantly degraded due to this loss of high frequency energy. This losses causes short (1 to 2 bit time) pulses to be narrowed in width (period) and reduced in height (amplitude).
One solution to this problem is to boost the high frequency components of a signal at the transmitter to compensate for the high frequency loss in the channel. This is frequently called transmit emphasis. But existing systems that employ transmit emphasis suffer from numerous disadvantages, as explained further herein.
Concomitantly, many receiver designs employ some sort of equalization to boost high frequency signals that are attenuated as the signal passes through the channel. This might be realized using a linear high pass filter, that boosts the high frequency signal was well any associated noise, and thus the signal-to-noise ratio (SNR) remains poor.
Another technique for handling attenuation of high frequency signals by communication channels is to employ decision feedback equalization/equalizers (DFE) at the receiver end, to help remove noise and distortion of digital signals, such as intersymbol interference (ISI) caused by attenuation of high frequencies. Some of the problems associated with digital signal processing as addressed by DFE are outlined in U.S. Pat. No. 6,437,932 to Prater et al., commonly assigned to the present assignee, and incorporated herein in its entirety.
Factoring all of the above, it can be seen that what is needed is a superior method and apparatus for reducing distortion in communication channels when transmitting digital data that contains high frequency signals in a mixed-signal communications channel.
To better understand the advantages of the present invention, FIGS. 2-3 disclose existing solutions, that the present invention improves upon.
Turning now to FIGS. 2A-2D, there are shown a idealized waveform diagrams for a typical system that employs transmit emphasis of a transmitted signal. The unemphasized transmit waveform sent by a transmitter, such as transmitter 10 in FIG. 1, is shown as waveform (A), FIG. 2A, labeled "Unemphasized Transmit Waveform". The received waveform received by a receiver, such as receiver 30 in FIG. 1, after channel distortion caused by a channel, such as channel 20 having transfer function H(s) in FIG. 1, is shown as waveform (B), labeled "Received Waveform", FIG. 2B. Waveform B has distortion, as can be seen by viewing bits 1, 9 and 13, inter alia, which have a height (amplitude component) and width (period component) less than ideal.
The idea behind transmit emphasis is for the high frequency components of the transmitted signal to be boosted at the transmitter side of the system, to compensate for the high frequency loss in the channel, so that the received signal will be improved. Thus the first bit of a digital pulse train, after each transition, is sent with a larger amplitude than subsequent bits, increasing the high frequency energy content relative to the low frequency energy content, since any transition or edge in a pulse train will have higher frequency components. This is shown graphically in FIG. 2C, as waveform (C), labeled "Emphasized Transmit Waveform". Thus, at pulse transition 3 to 4 (from left of waveform), where there is no transition from LOW to HIGH in the Unemphasized Transmit Waveform, (A) in FIG. 1, for the Emphasized Transmit Waveform, the fourth pulse bit (bit 3) has a slightly different height (amplitude) than the third pulse bit; likewise, at pulse 9 (bit 8); pulse 13 (bit 12); pulse 16 (bit 15), the amplitudes are slightly different at the transition from their neighbors, thus having different emphasis, in order to increase the high frequency energy content relative to the low frequency energy content.
The waveform received after transmission of the Emphasized Transmit Waveform (C) through the channel is shown in FIG. 2D as waveform (D), labeled "Received Waveform", which contains less distortion than received waveform (B), such as seen by comparing the two waveforms bits 1, 9 and 13.
The circuit to implement the Emphasized Transmit Waveform is shown in FIG. 3. A 2-tap FIR (Finite Impulse Response) filter is shown in the transmitter. The data to be transmitted, TXDATA, is retimed on clock line TXCLK and presented to the Main Transmit op-am driver 305 on timing signal line DOUT. The data to be transmitted is also delayed by the Delay flip-flop 309 and inverted, retimed and presented to the Emphasis driver op-amp 310 on timing signal line DOUTD for presentation to summer 312, with the aid of two Retiming Flip-Flops 307. As shown, the Emphasis driver 310 is has a programmable drive strength to control the amount of de-emphasis to increase the high frequency to low frequency energy content in the transition bits. The two driver outputs are combined at summer 312, with suitable inversion as necessary, as inversion generates de-emphases, to form TXOUT, the emphasized transmit signal output to the channel.
Notwithstanding the above, existing systems of transmit emphasis have several disadvantages in practice. In a transmit emphasis system such as shown in FIG. 2, ideally a system designer would set the transmit amplitude to maximize noise immunity, and then would use emphasis to increase the amplitude of the transition bits to improve the "eye" (a test pattern that measures the health of a communications channel). In reality, however, as semiconductor technology progresses, power supply voltages shrink. This makes it difficult to transmit large amplitude signals, so emphasis usually means transmitting maximum amplitude after the transitions and less than maximum amplitude on subsequent bits. The result is that in practice increased emphasis levels result in decreased available transmit amplitude.
Secondly, increasing the high frequency energy transmitted increasing the amount of crosstalk seen by receivers that may be nearby. This can turn a usable system into an unusable system.
Thirdly, increased high frequency energy in the transmit signal can exaggerate the effect of resonance in the channel and cause increased radiated EMI. Radiating EMI causes EMI compliance difficulties. Resonance can be due to reflections from connectors or stubs.
Fourthly, emphasis such as shown in the existing system of FIG. 3 requires at least one extra driver stage connected to TXOUT. This adds capacitance to the output, which reduces the bandwidth of the driver and increases reflections in the channel.
Lastly, channels that employ optics have additional amplitude limiting stages in the electro-optical conversion process. Amplitude modulation does not compensate past the electrical channel leading to the optics.
The present invention attempts to overcome the above-mentioned disadvantages and ameliorate the system of amplitude boosting high frequencies signals at the transmit end of a system employing a transmitter, communication channel and receiver.

System and method for transmit timing precompensation for a serial transmission communication channel


Described herein are systems, devices, and methods for determining a user's stride length and monitoring various aspects of the user's activities. An apparatus worn or carried by the user may determine and track when a user takes a step and, based at least in part on user-specific information, determine an estimated stride length of the user associated with a respective step rate or step rate range. The apparatus may further monitor the physical location, speed, or pace of the user during an activity and, in conjunction with step count information, determine a verified stride length for the user associated with a respective step rate or step rate range. The estimated and verified stride length determinations may be stored and used to determine one or more aspects of a user's subsequent activities, including but not limited to pace, speed, and calorie expenditure information, even when physical location information is unavailable.

Many portable and/or wearable devices have been developed for determining when a user takes a step during a fitness training session or other daily activity. Such devices and systems are now commonly found in so-called "activity trackers" and "health monitors." These devices typically comprise an accelerometer, e.g., a three-axis accelerometer, and software for interpreting raw data gathered by the accelerometer. The software may determine when a user has taken a step based on patterns identified in the accelerometer data, acceleration magnitudes that exceed predetermined thresholds, peak-to-peak threshold crossings in the data, dominant frequencies in the data, and/or a number of other known methods.
The step counting data can then be used in various applications, including but not limited to, recording the number of steps taken by the user during a monitored period (e.g., hourly, daily, weekly, etc.), estimating a number of calories burned by the user during the monitored period, and/or characterizing an activity level achieved by the user during the monitored period.
Step counting data can also be interpreted in conjunction with GPS tracking data collected by the portable or wearable device in order to calculate a stride length of the user. For example, a wearable device may determine that a user has taken a number of steps during the monitored period and traveled some distance. The user's stride length (SL) can then be calculated by dividing the distance traveled by the number of steps taken. Other information regarding the user's activity can also be determined using the GPS tracking data in conjunction with time, such as the user's pace (time/distance) and speed (distance/time).
Stride length, pace, and speed information become more difficult to calculate, however, when no GPS data is available, such as when no GPS signal can be received or when a user's position isn't changing (e.g., the user is running or walking on a treadmill). Accurate calculation of stride length may be further complicated based on the variance of a user's stride length at different paces or speeds. For example, a user's stride length may be shorter when running or walking at a first pace/speed than when the user is running or walking at a second, faster pace/speed.
Thus, a need exists for improved systems, devices, and techniques for determining, among other things, a user's stride length, pace, and speed, particularly when GPS information is limited or unavailable. Moreover, improved systems, devices, and techniques are needed to ensure the accuracy, reliability, and durability of such information.

Systems and methods for stride length calibration

BEIJING SHUNYUAN KAIHUA TECHNOLOGY LIMITED


A computer system executes a procedure by which a service broker accepts registration of interactive service; executes a procedure by which the service broker accepts a request from a client terminal to provide the interactive service; executes a procedure by which the service broker selects servers allowed to provide resources requested by the interactive service as candidates for the destination of arrangement of the interactive service; executes a procedure by which the service broker specifies a server as the destination of arrangement of the interactive service from the candidates for the destination of arrangement on the basis of the provision quality of the interactive service between each server and the client terminal; and executes a procedure by which the service broker arranges the interactive service stored in a memory, in the specified server.

The present invention relates to a method of arranging interactive service, a program of arranging interactive service, a recording medium for storing the program and a service broker.
A system in which a certain computer entrusts (arranges) a predetermined process to another computer is known widely. For example, according to JP-A-2004-38972, in a plurality of servers (described as "work stations" in JP-A-2004-38972) connected to one another by a network, a process unit (described as "grid calculation work load" in JP-A-2004-38972) is arranged on the basis of internal information of the servers such as frequencies in use.
According to JP-A-2004-38972, processing is performed in such a manner that a broker (described as "grid" in JP-A-2004-38972) selects a server allowed to execute the process unit on the basis of the processing capacity necessary for execution of the process unit and arranges the process unit in the selected server.
In the background art described in JP-A-2004-38972, when a process unit mainly including a numerical calculation process such as an arithmetic process is provided as a subject, the process unit can be executed by only processing in the inside of a server. Accordingly, the broker entrusting a process can allocate an appropriate server on the basis of information concerning the internal state of each server.
Incidentally, a service providing process is carried out between a server providing a service and a client receiving the service. Interactive service is the form of provision of service in which request messages and reply messages concerning service are transmitted and received frequently (several times) between a server and a client.
On the other hand, batch processing service is the form of provision of service in which the client's entrusting of service to a server is performed once collectively and in which the server's provision of service to a client is performed once collectively. The batch processing service is distinguished from the interactive service.
Accordingly, the interactive service is different from the batch processing service in that data concerning service are exchanged frequently between a server and a client. In the interactive service, the client's environment such as the quality of communication between the server and the client has a large influence on the provision quality of service.
Accordingly, when a process unit is used not for mainly performing numerical calculation but for providing interactive service (e.g. information retrieval service) to an end user, a problem occurs. That is, the background art has a problem that a server for providing service of an appropriate quality to an end user cannot be selected because there is no consideration for the end user using the interactive service when a server in which a process unit is arranged for providing interactive service is selected.
For example, assume that servers for achieving one information retrieval service are located in Tokyo and Osaka when a predetermined information retrieval service needs to be executed from a terminal located in Chiba. In this case, it is preferable that the server located in Tokyo is selected from the point of view of a small network delay. The server located in Osaka, however, may be selected. If the server located in Osaka is selected, convenience is lowered because the terminal located in Chiba receives service of a low quality (large network delay).

Method of arranging dialogue type service through interactive service system


A patient transporter having sponsons that provide buoyancy when deployed on water is provided. A sponson assembly formed by two sponsons connected to each other by a material, and which can be positioned beneath a patient transporter to provide buoyancy, is also provided.

1. Field of the Disclosure
The present disclosure relates to a patient transporter having sponsons to provide buoyancy.
2. Description of Related Art
One difficulty with a patient transporter, also called litter or stretcher, is that the transporters are not adapted for transporting the patient over lakes, rivers, streams, and other water tributaries. When carrying an injured person on a patient transporter across a tributary of water, the injured person and transporter must be physically carried by two or more personnel who are themselves attempting to navigate across the tributary. Also, in those instances where an injured person is carried on a patient transporter across a water tributary, the water can rise onto the transporter, or worse, can completely submerge the transporter and expose the person to further injury or even drowning.


Non-permanent occlusion of the uterine arteries is sufficient to cause the demise of uterine myomata without unnecessarily exposing other tissues and anatomical structures to hypoxia attendant to prior permanent occlusion techniques. A therapeutically effective transient time of occlusion of a uterine artery to treat uterine fibroid tumors is from 1 hours to 24 hours, and preferably is at least about 4 hours. A therapeutically effective temporary time of occlusion of a uterine artery to treat uterine fibroid tumors is from 1 day (24 hours) to 7 days (168 hours), and preferably is about 4 days (96 hours). By invaginating the tissues of the vaginal wall up to or around a uterine artery, collapse of the uterine artery can be achieved without penetrating tissue of the patient.

1. Field of the Invention
The present invention relates generally to the treatment of disorders which receive blood flow from the uterine arteries, and more particularly to methods for the non-permanent occlusion of the uterine artery or arteries, including for use in treating uterine myomata (fibroids), dysfunctional uterine bleeding (DUB), post partum hemorrhaging (PPH), and uterine bleeding associated with cesarian section surgery.
2. Brief Description of the Related Art
Hysterectomy (surgical removal of the uterus) is performed on approximately 600,000 women annually in the United States. For approximately 340,000 women, hysterectomy is probably the best current therapeutic choice for the treatment of their diseases (uterine cancer, endometriosis, menorrhagia, and prolapse). For approximately 60,000 women with dysfunctional uterine bleeding (abnormal menstrual bleeding that has no discrete anatomic explanation such as a tumor or growth), newer endometrial ablation techniques may be an alternative to hysterectomy. For approximately 200,000 women with benign but symptomatic (excessive bleeding, pain, and "bulk" sensations) muscular tumors of the uterus, known as leiomyoma or fibroids, newer treatment methods have been developed which may spare these women a hysterectomy, as well.
Hysterectomy for treating uterine fibroid disorders, though effective, has many undesirable characteristics. Thus, any method which can approximate the therapeutic result of a hysterectomy without removing the uterus (and commonly the ovaries since they are closely adjacent to the uterus) would be a significant improvement in this field.
The undesirable characteristics of hysterectomy include a known mortality rate of 0.5 deaths per 1000 hysterectomies. Stated another way, the risk of death within 30 days of hysterectomy is thirty times greater for women who have had a hysterectomy than for women of similar ages and backgrounds who have not had a hysterectomy. Morbidity (medical symptoms and problems short of death) associated with hysterectomy include possible injury to adjacent organs (the bladder, the ureters, and bowel), hospital stay of approximately one week, five to six weeks of slow recovery to normal activity, three weeks of absence from work, direct medical expenses of at least $10,000, indirect cost of time away from work, a future three-fold increase in the incidence of cardiovascular disease, decreased sexual pleasure in approximately thirty percent of women, and depression and anxiety for many years after the hysterectomy for approximately eight percent of women.
Surgically removing fibroids (myomectomy) or in situ ablation of uterine fibroids is a bit like eradicating ants in the pantry—they are not all seen from one perspective and there may be a lot of them. Commonly, a diagnosis of uterine fibroids involves the presence of multiple fibroids, often averaging ten fibroids or more per afflicted uterus. Consequently, it is difficult to know which fibroid is causing symptoms to the patient (bleeding, pain, and bulk effects on adjacent organs). Furthermore, fibroids occur at different layers in the uterus. Uterine fibroids can occur adjacent to the lining of the uterus (submucosal fibroid), in the myometrium (intramural fibroid), or adjacent to the outer layer of the uterus (subserosal fibroid). Consequently, if one is directly observing the uterus from the peritoneal cavity, only subserosal fibroids would be seen. If one is directly observing the uterus from the endometrial surface of the uterus, only the submucosal would be seen. Fibroids deep within the wall of the uterus are poorly visualized from either surface. Finally, since fibroids come in all sizes, only the larger fibroids will be seen in any case.
Clearly, the strategy of identifying which individual fibroid is causing symptoms (when there are often many), finding that fibroid, and then either removing or destroying that individual fibroid is a rather complex strategy. It is therefore easy to understand why the hysterectomy is such a common surgical choice. With hysterectomy, all uterine fibroids are removed in one stroke.
In 1995, it was demonstrated that fibroids, in a uterus that contained one or multiple fibroids, could be treated without hysterectomy using a non-surgical therapy, specifically comprising bilateral intraluminal occlusion of the uterine arteries (Ravina et al., "Arterial Embolization to Treat Uterine Myomata", Lancet Sep. 9, 1995; Vol. 346; pp. 671–672, incorporated by reference in its entirety herein). This technique is known as "uterine artery embolization". The technique uses standard interventional radiology angiographic techniques and equipment, whereby the uterine arteries are accessed via a transvascular route from a common femoral artery into the left and right uterine arteries.
Three facts explain the success of uterine artery embolization. First, it has been established that pelvic bleeding from a wide variety of sources (e.g., auto accidents, surgical errors, and post partum hemorrhage) can be effectively controlled with embolization techniques using coils placed in arterial and venous lumens (U.S. Pat. Nos. 4,994,069, 5,226,911, and 5,549,824, all of which are incorporated in their entireties herein) (available from Target Therapeutics), or particles (GELFOAM pledgets, available from Upjohn, Kalamazoo, Mich., or IVALON particles, available from Boston Scientific).
Second, fibroids live a tenuous vascular life with very little ability to recruit a new blood supply from the host when the primary blood supply is compromised. Third, the uterus has a dual (or redundant) blood supply; the primary blood supply is from the bilateral uterine arteries, the secondary blood supply from the bilateral ovarian arteries.
Consequently, when both uterine arteries are occluded, i.e., bilateral vessel occlusion, the uterus and the fibroids contained within the uterus are both deprived of their blood supply. However, as demonstrated by Ravina et al., the effect on the fibroid is greater than the effect on the uterus. In most instances, the fibroid withers and ceases to cause clinical symptoms.
The uterine artery embolization technique utilized by Ravina et al. uses standard transvascular equipment, available in a typical interventional radiology angiography suite. This equipment includes guide catheters to selectively enter the tortuous right and left uterine arteries, Ivalon or Gelfoam particles, and intravascular coils. With skill and these standard angiographic tools, the uterine arteries can be occluded bilaterally and fibroid disease treated through a 2 mm hole in the right groin and through the right common femoral artery. Following the procedure, the arterial puncture site is held with manual pressure for fifteen minutes. While post-procedural pain is often significant, and requires intravenously delivered pain medication, the patient is typically fully recovered in a number of days.
The problem with uterine artery embolization is simple. The physicians who know how to do the procedure are interventional radiologists, who do not take care of gynecology problems. The physicians who take care of gynecology problems do not possess the skill necessary to perform catheter-based uterine artery embolization. Accordingly, only on the order of tens of thousands of uterine artery embolizations have been performed, worldwide, since approximately 1995, whereas hundreds of thousands of hysterectomies have been performed each year for uterine fibroids which are symptomatic.
Currently, many physicians continue to embolize the uterine artery with PVA particles. As reported by the Society for Cardiovascular and Interventional Radiology in late 1999, some 6000 cases have been performed within the United States. Currently the annualized run rate for this procedure is approximately 4500 cases per year.
Previously, physicians have permanently, surgically ligated the uterine artery utilizing metal vascular clips. This procedure has been performed laparoscopically and requires a great deal of surgical skill to access, identify, dissect, and ligate the uterine arteries. This requirement for high skill and a full surgical approach has limited the use of surgical ligation of the uterine arteries as a clinical alternative for uterine fibroid treatment.
The current treatments offered to women focus on permanent or near permanent occlusion methods for the uterine artery. These methods include (the expected longevity of the embolic agent is given parenthetically): embolizing with PVA particles (6 months to permanent in situ); embolizing with stainless steel coils (permanent in situ); embolizing with Gelfoam (3 to 4 weeks before degradation of the embolic particles); surgical ligation with metal vascular clips (permanent); and surgical ligation with RF ablation (permanent).
All of the prior art devices and methods are therefore aimed at permanent occlusion of the uterine artery, resulting in redirection of the blood flow to the uterus through collateral circulation. The patients which suffer most dramatically from uterine myomata are women of child bearing age who may desire to bear additional children. The current methods of embolizing or ligating uterine arteries are specifically contraindicated for women who desire to bear additional children. This is the realization of inadequate blood supply to the uterus because of the loss of the uterine arteries, the primary blood supply. A few reports have been cited of women who have undergone uterine artery embolization with PVA particles and then gone on to become pregnant and deliver normal babies. Reports have also been cited of women who have experienced premature menopause due to ovarian failure from these same procedures.
While it is apparent that uterine artery embolization with the current embolic agents or ligation techniques is effective for treating uterine myomata, it is also apparent from a review of case reports and complications that this treatment is in need of a substantial improvement in safety.
The tissue of the vaginal wall is very elastic, pliable, and flexible. The vaginal wall can made to assume different shapes without tearing and without significant patient discomfort or pain. Heretofore, this inherent characteristic of these tissues has not been utilized in the treatment of myomata, or for accessing the uterine artery. Instead, prior techniques have relied upon transvascular routes (Ravina et al.), complete surgical or laparoscopic dissection of the tissues surrounding a uterine artery to achieve access to the vessel. The difficulty and cost associated with the use of traditional transvascular access, and the possibility of infection and surgical complication associated with dissection, render these prior techniques unacceptable.
Those of skill in the art are well acquainted with DUB, PPH, and cesarian section-related bleeding. While the causes of DUB are often not identified, current treatments include endometrial ablation and hysterectomy, which can be extreme treatments for some patients. PPH and cesarian section-related bleeding can be a dangerous if not quickly and adequately controlled, which may require a fast surgical response, from which the patient may suffer from associated trauma of the surgery.
Another aspect of hysterectomy procedures is that the blood supply to the uterus is typically stopped by ligating the uterine arteries, to prevent the patient from bleeding excessively as the uterus is removed. This ligation task can be very laborious and time-consuming, as the arteries are dissected and ligated by the surgeon, and have associated complications.
There therefore still remains a need in the art for improvements in methods, processes, and techniques for occluding the uterine arteries for treatment of numerous conditions and/or facilitating other procedures.

This patent is subject to a terminal disclaimer.

Methods for minimally-invasive, non-permanent occlusion of a uterine artery


An apparatus for delivering medicaments to a patient which include a fluid dispensing device and a novel cooperating reservoir fill assembly which can be easily and quickly connected to the fluid dispensing device. The fluid dispensing device uniquely includes an elastomeric bladder stored energy type infusion means which can be used for delivering a wide variety of medicaments such as drugs, medicaments, bilogical agents, or other therapeutic agents at a substantially constant rate.

1. Field of the Invention
The present invention relates generally to infusion devices. More particularly, the invention concerns an elastomeric bladder type infusion device and cooperating reservoir fill assembly. The infusion device of the invention is used for delivering a beneficial agent to a patient at a substantially constant rate.
2. Discussion of the Prior Art
A number of infusion pumps embodying an elastomeric balloon or bladder for delivery of a quantity of pharmaceutically active material to a patient have been suggested in the past. For example U.S. Pat. No. 4,915,693 issued to Hessel discloses an infusion pump comprising an elastomeric bladder having at least an open end and an elongated stress member extending concentrically within the entire length of the hollow portion of the bladder and having a fluid tight seal therewith. Both a filling port and an exit port are provided in the stress member, each in fluid communication with the interior of the bladder by way of an influent and an effluent lumen respectively. The stress member has a diameter that is greater than the relaxed internal diameter of the bladder, and has a length that exceeds the relaxed internal length of the hollow portion of the bladder so that it prestresses the bladder in both the axial and radial directions, when disposed therein, substantially filling the bladder in its unfilled state. The Hessel device also includes a one-way valve in the stress member which permits flow in the influent lumen only in the direction of the interior of the bladder.
Another type of balloon infusion devise is disclosed in U.S. Pat. No. 4,386,929 issued to Perry et al. The Perry et al device has spaced apart inlet and outlet means and the bladder, which is capable of expanding and contracting radially and axially upon inflation and deflation. When deflated, the lumen of the bladder is substantially completely filled by lumen filling means which protect the bladder from being punctured by the hypodermic needle used to fill and inflate the bladder. The lumen filling means resists the compressive load applied during insertion of the needle and maintains the inlet and outlet means in spaced apart relationship while providing substantially no resistance to the axial expansion of the bladder. By having the lumen of the bladder filled with the lumen filling means when the bladder is deflated before its subsequent inflation and deflation, substantially complete expulsion of the fluid contents of the bladder can be obtained.
Very early balloon type devices are described in U.S. Pat. Nos. 3,468,308 and 3,469,578 issued to Bierman. These patents describe a device for expelling a liquid from a bladder member at an extremely slow rate over an extended period of time. In the device described in U.S. Pat. No. 3,469,578, the liquid is expelled slowly by pressure induced on the liquid by the internal stresses of the distended bladder member. In the device disclosed in U.S. Pat. No. 3,468,308, the liquid is expelled by pressure control means which controls pressure applied to the exterior of the bladder member to control its rate of collapse.
In the devices described in both of the aforementioned patents, the bladder member comprises a balloon, or tube-like member which is typically distendable both length wise and laterally when initially pressured. Admission and discharge of liquid is of necessity through a single neck, or outlet portion of the balloon-like bladder.
Among the more unique infusion devices ever developed are those described in U.S. Pat. Nos. 5,163,940 and 4,354,278 which were issued to the present inventor. Still another novel prior art infusion device is described in U.S. Pat. No. 5,700,244 which patent was also issued to the present inventor. Because the apparatus of the present invention constitutes an improvement over the apparatus described in the U.S. Pat. No. 5,700,244, this latter patent is hereby incorporated by reference as though fully set forth herein.

Fluid dispenser with reservoir fill assembly


A lamp is provided having terminal pins mounted on and extending outwardly along a longitudinal axis of an end cap of the lamp. The pins are offset relative to one another along the longitudinal axis. The end cap has semi-circular, parallel surfaces at one end, and the pins extend outwardly from the respective semi-circular, parallel surfaces. A barrier wall extends substantially perpendicularly between the semi-circular surfaces. In a first embodiment, a male extension member extends outwardly from the barrier wall along at least a portion of the lower semi-circular surface. This male extension is coextensive with the upper semi-circular surface. Alternatively, in a second embodiment, a female recess is provided through the boundary wall. This recess again extends between the upper and lower semi-circular surfaces.

1. Field of the Invention
This invention generally relates to improvements in lamps, especially ultraviolet lamps used in air and water purifiers.
2. Description of Related Art
Ultraviolet air and water or other liquid purifiers are known for disinfecting contaminated air or water or other liquid for domestic or commercial use. Such purifiers include at least one lamp for emitting ultraviolet radiation into a chamber filled with contaminated air or water or other liquid to kill microorganisms therein. In conventional manner, the lamp includes two electrodes spaced apart within an elongated arc tube containing a gas, particularly mercury vapor with or without additives. A pair of end caps are mounted at the ends of the tube. Each electrode contains two lead wires from the lamp seal each of which, or in some instances only one, are electrically connected to respective contact(s) or terminal pin(s). The lamp is typically inserted endwise into a sleeve installed in the water, other liquid or air purifier with or without the sleeve. To simplify insertion and electrical connection, the pins are conveniently mounted on one of the end caps. When the electrodes are energized by voltage from an electrical power supply, an electrical discharge is initiated in the gas between the electrodes. This discharge reacts with a layer of a radiation-emitting material coated on an interior surface of the arc tube and causes ultraviolet radiation to be emitted from the lamp in a manner well known in the art.
An example of an ultraviolet lamp of the type described above is disclosed in U.S. Pat. No. 5,166,527 ('527), all of the contents of which are incorporated herein by reference. The '527 patent discloses a lamp, especially useful as an ultraviolet lamp for use in a water purifier, comprising an elongated, hollow arc tube extending along a longitudinal axis between opposite end regions. The tube contains a gas, preferably mercury vapor with or without additives. A pair of electrodes is spaced apart along the longitudinal axis. The electrodes are respectively mounted within the arc tube at the end regions thereof. A pair of end caps is respectively mounted at the end regions of the arc tube. A first electrical contact or pair of electrical contacts or terminal pins extends in mutual parallelism along the longitudinal axis and is electrically connected to one or both of the electrode lead wires. A second electrical contact or pair of electrical contacts or terminal pins extends in mutual parallelism along the longitudinal axis and is electrically connected to one or both of the other of the electrode lead wires. Both pairs of pins are mounted on, and extend outwardly along the longitudinal axis of, one of the end caps. A wire conductor is, or two wire conductors are, located exteriorly of the tube and electrically connected to one pin or one pair of pins at one end region of the tube, as well as to the electrode at the other end region of the tube.
Two embodiments, of the lamp disclosed in the '527 patent are shown in prior art FIGS. 1 and 2. As shown in FIGS. 1 and 2, the pairs of pins are offset relative to each other along the longitudinal axis. This offset resists the formation of an electrical arc between the pairs of pins exteriorly of the arc tube, especially in the presence of the moisture-laden, humid environment of the water purifier.
Still referring to prior art FIGS. 1 and 2, the one end cap has a stepped outer end wall having a pair of wall portions lying in mutual parallelism in planes generally perpendicular to the longitudinal axis. The first pair of pins is supported on, and extends through, one of the end wall portions for a predetermined distance, and the second pair of pins is supported on, and extends through, the other of the end wall portions for the same predetermined distance. The planes of the end wall portions are spaced apart by a predetermined spacing larger than said predetermined distance in order to still further prevent electrical arcing between the pairs of pins exteriorly of the arc tube. A barrier wall internally of the one end cap physically separates the electrical connections to the two pairs of pins to resist the formation of an electrical arc between the pairs of pins interiorly of the one end cap. The barrier wall is advantageously made of the same non-conductive material as the one end cap.
In addition to the two-tiered stepped bases of the '527 patent, other multi-tiered bases have been manufactured including those bases shown in prior art FIGS. 3-7.
Although well-suited for their intended purposes, there continues to be a need for improved lamp base designs, particularly ultraviolet lamps.

Ultraviolet lamp for use in water purifiers


An air bag module using a tubular inflator uses a different housing, retaining ring, cushion and inflator bracket than are currently used, with the appearance and function of the module not being changed but only the internal components. The inflator is placed in a slotted section of the module housing with the diffuser thereof protruding from the center through a hole in a raised portion of the module housing slotted section, which hole is sized closely to the size of the diffuser. The diffuser extends directly into the module at a 90.degree. angle to the plane surface of the housing. The retaining ring has raised portions in the center thereof to match the raised portion of the module housing, has holes in the raised portions, and has tabs which extend through holes in the cushion and the module housing. The module housing has tabs on the raised portion thereof which extend through holes in the cushion and retaining ring. The cushion uses a rectangular mounting so that the cushion can match the radius of the module housing in the raised portion which goes over the tubular inflator. The retaining bracket extends around the back side of the inflator to hold it in place and includes cover retaining brackets incorporated therein. Studs which hold the module together extend from the retaining ring through holes in the cushion, module housing, and retaining bracket.

1. Field of the Invention
This invention relates to an air bag module for use on the driver side of automotive and other vehicles wherein an inflatable air bag or cushion is inflated in the event of a collision to protect the driver from injury that could result from being forcibly thrown against the steering wheel, dashboard, etc. The air bag module uses a tubular inflator assembly.
2. Description of the Related Art
Inflator assemblies that currently are in use in driver side air bag modules, as disclosed, for example, in U.S. Application for Patent bearing Ser. No. 07/820,826, filed Jan. 15, 1992 by Gary V. Adams and Bradley W. Smith, pending typically are toroidal types having flat, disk-like shapes with the dimensions of the inflator assembly typically being about two inches (2") thick and four inches (4") in diameter, much of the inflatable cushion stored in the air bag module is folded in front of the inflator assembly as opposed to the sides thereof. While an inflator assembly having a tubular shape would allow much of the cushion to be folded on the sides thereof in an air bag module, a tubular inflator assembly will not fit in driver side air bag modules as they are currently designed.
Inflator assemblies of the toroidal type produce a cushion inflating gas source from a combustible gas generating material which, upon ignition, generates a quantity of gas sufficient to inflate the cushion. One form of tubular inflator assembly similarly is operative to generate gas for inflating cushions from a combustible gas generating material. In another form of tubular inflator assembly, however, the cushion inflating gas results from a combination of stored compressed gas and a gas generating material. The latter form of tubular inflator assembly is commonly referred to as an augmented gas or hybrid inflator. Hybrid inflators affect the performance of air bag modules in several ways including variation in the amount of stored gas, the transmission of heat to the stored gas and the rate at which the inflating gas is dispensed into the inflatable cushion.
There is a need and a demand to provide a driver side air bag module in which a tubular inflator assembly may be used to facilitate folding of much of the cushion on the sides of the inflator and to affect the performance of the air bag module. The present invention was devised to fill the technological gap that has existed in the art in these respects.

Air bag module with a center mounted tubular inflator


A memory device includes a latch component including a first input configured to receive a functional data bit associated with a functional operation, a second input configured to receive a memory test/repair data bit associated with a memory test operation, and a latch comprising a data input and a data output and select logic configured to selectively connect one of the first input or the second input to the data input of the latch based on a mode of operation of the memory device. A method includes operating a memory device in a first mode associated with a memory test operation and in a second mode associated with a functional operation. The method further includes storing a memory test/repair data bit at a latch component of the memory device in the first mode and storing a functional data bit at the latch component in the second mode.

Many memory devices utilize memory built-in self-test (BIST) techniques whereby some or all of the memory storage locations are analyzed by embedded circuitry to identify faulty memory storage locations. Repair information regarding the faulty memory storage locations (e.g. the addresses of the faulty memory storage locations) is stored in a set of latches dedicated to the storage of test information only. The repair information then can be retrieved from these dedicated latches for the purpose of repairing the faulty memory storage locations, such as by rerouting the corresponding address to a back-up memory storage location. However, as the storage capacity of memory devices increases, so does the number of dedicated latches needed to store the test information. This increase in the number of latches dedicated to storing memory test information has resulted in a corresponding increase in the size, complexity, and cost of conventional memory devices.
In an effort to reduce the number of dedicated latches, some memory devices divide their memory arrays into separate regions for testing and run multiple passes of the test process. After each pass, the repair information for the tested region is shifted out for the next test pass, thereby reducing the size of the repair information for each pass, and thus the number of dedicated latches needed to store the repair information. However, this technique is complex and inefficient due to the repetition of the test process. As an alternate technique, some memory devices utilize a compression engine to compress the test information to fit into a smaller number of dedicated latches. However, like other conventional solutions, the implementation of the compression engine increases the complexity of the memory device and reduces the performance of the test process. Accordingly, an improved technique for storing test information for memory test and repair purposes would be advantageous.

Shared latch for memory test/repair and functional operations


From top to bottom of an inner wall of a case in which stacked stapled sheets each composed of linear staples connected in parallel are accommodated, horizontal nonreturn projections are successively arranged. A nonreturn lug is attached to a staple pushing plate pushing the staple sheets by a spring, and the nonreturn lug is engaged with the nonreturn projections of the case. The nonreturn lug and the nonreturn projections are shaped to permit a descent of the staple pushing plate and inhibit an ascent thereof. In addition, a height of an apex of each of the nonreturn projections is reduced step-wise or with no step from top to bottom of the inner wall of the case.

An electric stapler in which stacked staple sheets each composed of linear staples connected in parallel are loaded is used as not only a stand-alone stapler but also incorporated in a copier or post-printing processor.
As a kind of electric stapler, there has been proposed an electric stapler using a staple magazine in which stacked staple sheets are loaded. In this electric stapler, when the staples are used up, an entire magazine is replaced. JP-A-2004-237446 discloses an electric stapler in which for the purpose of resource-saving, a staple for refill is received within a case of plastic paper, and the case is loaded in a staple magazine or an electric stapler body.
The staple for refill proposed in JP-A-2004-237446 is provided with a plate-shaped pushing member for pushing staple sheets within a plastic case from above. When an arm or spring provided in the staple magazine or the electric stapler body depresses the pushing member, the pushing member is brought into elastic contact with an upper face of the staple sheets. Thus, a staple sheet on a lowermost layer is stably fed to a forming-and-driver mechanism.
The staple for refill proposed in JP-A-2004-237446 is accommodated in a plastic case and has a structure in which a plate-shaped pushing member is placed on an upper face of the staple sheets. A depressing means such as a spring for urging the pushing member is provided on a side of the staple magazine or the electric stapler body. Therefore, in a state where the depressing means is not loaded in the staple magazine or electric stapler, pushing of the staple sheets is released so that the staple sheets may move up and down, or fly out from the staple forwarding mouth of the case.
In order to obviate such an inconvenience, in accordance with a related art of this application which is not a prior art, sawtooth nonreturn projections are arranged vertically in parallel on an inner wall of the case and a nonreturn lug engaged with the nonreturn projections are provided on a plate-shaped pushing member so that a rise of the plate-shaped pushing member is limited. In accordance with this related art, a component such as a spring is not required so that the structure is simple. In addition, since the metallic component is not used, disposal processing can be easily carried out.
However, in this case, since depressing of the plate-shaped pushing member while the electric stapler is used is entrusted to a spring on a side of a staple magazine or a stapler body, as the staple sheets are consumed and the plate-shaped pushing member descends, a load of the spring decreases so that an elastic force of the spring is problematically reduced.
Specifically, as a result that the spring on the electric stapler depresses the plate-shaped pushing member, when the nonreturn lug of the plate-shaped pushing member warps and climbs over the nonreturn projections, a certain load is applied. If the plate-shaped pushing member is located at a relatively raised position (when there are many remainders of the staple sheets), the spring is compressed to provide a large elastic force so that depressing of the plate-shaped pushing member is not problematic. However, as the plate-shaped pushing member descends owing to consumption of the staple sheets, the spring is expanded and so its elastic force is also reduced. In this case, the nonreturn lug of the plate-shaped pushing member cannot climb over the nonreturn projections so that the plate-shaped pushing member may not be in pressure-contact with the staple sheets.


An organic electroluminescent display device including a first electrode and a second electrode formed on a substrate, and a plurality of organic film layers between the first and second electrodes, including a first organic film layer provided between the emitting layer and the second electrode, and a second organic film provided between the emitting layer and the first organic film layer, wherein the first organic film layer includes a first organic metal complex compound, and the second organic film layer includes a mixture of a charge carrier transport material and a second organic metal complex compound.

1. Field of the Invention
The present invention relates to an organic electroluminescent display device, and, more particularly, to a display device that has a low driving voltage, superior life span characteristics, and is stabilized to the external environment due to an improved electron transport layer and electron injection layer.
2. Description of Related Art
Recently, the organic electroluminescent display device is being noticed as a next generation display device owing to various qualities such as its narrow thickness, wide viewing angle, light weight, small size, fast response time, and low power consumption compared with a cathode-ray tube (CRT) or liquid crystal device (LCD).
Particularly, an organic electroluminescent display device has a quality of being easily fabricated through a simple fabrication process, due to its simple structure of an anode, organic film layer, and a cathode. The organic film layer consists of various layers according to functions, and may generally comprise a hole injection layer, a hole transport layer, a luminescent layer, an electron transport layer, and an electron injection layer.
In FIG. 1, holes are injected from the anode 7, which is a transparent electrode, so that the injected holes are transferred to an emitting layer 4 which is one of organic film layers 10 through a hole injection layer 6 and a hole transport layer 5, and electrons are injected from a cathode 1 so that the injected electrons are transferred to the emitting layer 4 through an electron injection layer 2 and an electron transport layer 3. The transferred electrons and holes are bonded in the emitting layer 4 to emit light.
There are methods for improving an electron transport layer and an electron injection layer in order to improve the driving voltage and life span of an organic electroluminescent display device. According to U.S. Pat. No. 5,776,622, characteristics of a device were improved by depositing a dielectric material such as LiF, BaF2 and CsF to a thickness of about 1 nm between an electron transport layer and a metallic electrode to improve driving voltage.
Kido, et al., of Japan announced results in which a driving voltage was reduced by using a layer in which a material in the alkaline metal series, such as Li, is doped on an organic electron transport layer adjacent to the cathode as an electron injection layer (SID 97, Digest, page 775).
The reduction of the driving voltage by the doping of an alkaline metal results from the fact that electrons are more smoothly injected by removing an electron injection barrier from the cathode. However, the material in the Li series has a problem in that it is sensitive to oxidization, and is diffused to a large extent. Furthermore, a finely controlled doping concentration is required, since the concentration of a doping metal has an influence on the characteristics of a device in the case of metal doping.
Disclosed in U.S. Pat. No. 6,396,209 is a structure in which a mixed layer of an electron transporting organic compound and an organic metal complex compound is used as an electron injection layer, and a metal is deposited on the mixed layer to improve the characteristics of an organic electroluminescent display device. Using this electron transporting organic compound and the organic metal complex compound could reduce the driving voltage.
However, a structure of a new device for obtaining more stable device characteristics is required, since the methods discussed above have a high degree of difficulty in the depositing process, and also have a low device stability.

Organic electroluminescent display device having bi-layer electron injection structure


Embodiments of the present disclosure are direct to a low-carbon chromium steel, and methods for manufacturing said steel, having a low vanadium concentration. In some embodiments, the steel can have high corrosion resistance while retaining adequate strength and toughness. The steel can be manufactured through an austenitization process, followed by quenching at a controlled cooling rate, and tempering to form about 5 to 10% bainite, while limiting formation of chromium rich carbides.

1. Field
Embodiments of the present disclosure relate to the composition and manufacturing of low carbon steel tubes with high corrosion resistance.
2. Description of the Related Art
Corrosion has a wide range of implications on the integrity of materials used in the oil industry. Among the different ways in which corrosion may appear there is the so-called "sweet corrosion" that occurs in media rich in CO2. This is one of the prevailing ways of corrosion that must be faced when producing oil and gas.
The damage produced by corrosion caused by CO2 has an impact on capital and operational investment, as well as on health, security, and environmental impact. Many of the failures occurring in the oil wells are the result of the corrosion caused by CO2.
Steels having a high resistance to corrosion have been developed to manufacture pipes for oil and/or gas exploration and production in the petroleum industry. For example, low-carbon steels having an improved resistance to corrosion have been developed for applications in the oil industry and particularly in environments containing CO2. Nevertheless, further improvements in the manufacturing, corrosion resistance, cost of raw materials and other properties of such steels are still desired.

Low-carbon chromium steel having reduced vanadium and high corrosion resistance, and methods of manufacturing