A board 20 is provided with a Cu film 30 as a conformal mask, in which are formed a register mark 30b and an opening 3a through which a via hole is formed. A camera senses this register mark 30b so that the position of the board 30 is determined. A laser beam is directed to the approximate position of the opening 30a, so that the opening 26a through which the via hole is drilled is formed. The accuracy of the position of the opening of the via hole depends on the accuracy of the position of the opening 30a in the Cu film 30 as the conformal mask. Therefore, the via hole can be formed at an adequate position despite the low accuracy of the position for laser irradiation.

A build-up multilayer wiring board alternately has interlayer resin insulators and conductive circuit layers, provides holes to the interlayer resin insulator layers, and then electrically connects the upper layers and lower layers by forming conductive films on the surface of the walls of these holes.
A hole (via hole) in the interlayer resin insulating layer is generally formed with the use of an exposure and developing process, which gives photosensitive property to the interlayer resin.
However, the required diameter of these via holes in a multilayer printed wiring board is almost 100 μm or less, thus it is necessary to develop technology which makes it possible to maintain this small diameter. Due to such stringent requirements, the employment of a processing method utilizing a laser beam for the boring of the holes in the build-up multilayer wiring board will now be investigated.
Technology using laser for boring is proposed, in JPA HEI 3-54884. According to this method, a light beam from a laser source is received by a processing head for deflection. Thereby, the laser beam is irradiated to a predetermined resin insulator to form a hole.
In mass production of multi-layer printed wiring boards, which have hundreds to thousands of via holes in each layer, efficient hole drilling is essential. In addition, via holes need accurate positioning for electrical connection to conductor circuits in the layers below.
Unfortunately, it has been difficult to control, with high accuracy, the position of laser irradiation for via hole drilling in mass production. This has aroused a need for a process for fabricating a multi-layer printed wiring board containing openings at accurate positions. However, the current method of manufacture can not guarantee accurate positioning of laser irradiation. Improvement in positioning accuracy is offset by a necessary decrease in head driving speed, which in turn lowers productivity.
The present invention aims to address the above-mentioned problems. It is an object of the present invention to provide a process for producing a multi-layer printed wiring board, said process permitting accurate positioning of via holes independent of the accuracy of position for laser irradiation, thereby drilling a large number of holes efficiently by laser irradiation.
It is another object of the present invention to provide a method for increasing the driving speed of the scanning head without decreasing the accuracy of positions of via holes.

Process for producing a multi-layer printed wiring board


A compact, inexpensive, large-capacity ozone generator with increased ease of apparatus maintenance. An ozone power supply includes an n-phase inverter for obtaining an AC voltage having a predetermined frequency and outputting an n-phase AC voltage waveform; n reactors and an n-phase transformer for converting an n-phase AC voltage to a high AC voltage; n high-voltage terminals for outputting the n-phase high AC voltage; and a low-voltage terminal having a common potential. Ozone generator units are electrically divided into n pieces within a discharge chamber. Each ozone generator unit includes n high-voltage electrode terminals and one low-voltage electrode terminal, common to all ozone generator units. Each ozone generator unit supports an n-phase AC discharge to generate ozone.

A conventional large-capacity ozone generator is typically configured as shown in FIG. 10 to construct a several-tens-to-several-hundreds-of-kilograms-per-hour class, large-capacity ozone generator. This large-capacity ozone generator is adopted to use ozone for advanced sewage treatment and pulp bleaching.
FIG. 10 shows an example of a conventional, large-capacity ozone generator that generates ozone at a rate of 35 kg/h. The conventional large-capacity ozone generator 1100 includes a water tank for cooling, a huge tank (3000 mm in diameter and 4500 mm in length) filled with an oxygen material gas, and 600 cylindrical glass high-voltage pipes 5, which are 40 mm in diameter and 2000 mm in length. A cylindrical high-voltage electrode pipe is mounted in the cylindrical glass high-voltage pipes. The cylindrical high-voltage electrode pipe is coated with a high-voltage electrode 3.
The reference numeral 2000 denotes a transformer for supplying a high voltage to the plurality of cylindrical glass high-voltage pipes 5. The reference numeral 3000 denotes a plurality of series-connected reactors for suppressing an inverter output current. The reference numeral 4000 denotes a single-phase inverter element for outputting a single-phase AC voltage from a DC voltage input. The reference numeral 5000 denotes a converter (rectifier) for supplying a DC voltage that is to be input into an inverter. The reference numeral 6000 is an input transformer for cutting off a third harmonic, which arises out of a load on a three-phase commercial AC power supply and ozone generator. The reference numeral 4100 denotes a drive circuit for driving the inverter element 4000. The reference numeral 4200 denotes a control circuit for the inverter element 4000. The reference numeral 4300 denotes a computer for exercising management and issuing condition setup instructions concerning, for instance, the status of the ozone generator and the current output to the inverter. FIG. 11 schematically indicates the number of 40 mm diameter cylindrical glass pipes 5 that can be mounted within a cross section 200 mm square. FIG. 12 is a characteristics diagram illustrating the relationship between an inverter instruction signal and inverter output waveform.
In the conventional large-capacity ozone generator, a three-phase commercial AC power supply enters the input transformer 6000. A converter 5000 converts the output of the input transformer 6000 to a DC voltage. The obtained DC voltage enters the inverter element 4000. The inverter element 4000 converts the DC voltage to an AC voltage having a frequency of approximately 1 kHz.
The inverter element 4000 receives ozone performance conditions from the computer 4300 and forwards them to the control circuit 4200. The control circuit 4200 creates an inverter control signal. Predetermined control signals are alternately input from the drive circuit 4100 to the inverter element 4000 as the ON-OFF signals for two instruction signals 7001a, 7001b shown in FIG. 12. The inverter then outputs an AC rectangular voltage that is synchronized with the resulting pulse.
When the AC rectangular voltage enters the transformer 2000 via the series-connected reactors 3000, which suppress the inverter output current, the secondary side of the transformer outputs a high-voltage AC waveform Y1, which has a voltage of approximately 10 kV and is similar to a 1 kHz sine waveform. This high-voltage AC waveform is applied to the plurality of cylindrical glass high-voltage pipes 5 from a high-voltage terminal 120 of the large-capacity ozone generator 1100. Another low voltage of a secondary voltage is connected to a ground terminal (low-voltage terminal) YG of the large-capacity ozone generator 1100. When a high voltage is applied to the ozone generator 1100 as described above, a silent electric discharge occurs between the high-voltage electrode 3 and low-voltage electrode via the cylindrical glass high-voltage pipes 5, which are dielectrics. Consequently, ozone is generated so that an ozonized gas can be obtained from an ozone outlet 110 of the ozone generator 1100.
The performance specifications for the above conventional ozone generator 1100 are as indicated in Table 1 if it is a 35 kg/h class, large-capacity ozone generator. The large-capacity ozone generator is a huge apparatus, which has a diameter of 3000 mm, a length of 4000 mm, and a cubic capacity of 28 m3. Further, the power supply capacity is 452 kW. The load power factor is approximately 30%. Therefore, the load current is 150 A. The load voltage is 10 kV. The load capacity is 1500 kVA. It means that the transformer 2000 is extremely large.
TABLE 1Conventional cylindrical multi-pipe method specificationsDischarge cell cubic volume20 cm × 20 cm × 20 cm(0.003 m3)Number of discharges600 (φ40-2000)Discharge area (m2)150.72Ozone generator tank cubicφ3000-4000 mm (28 m3)capacityRated ozone concentration(g/m3)180Maximum ozone concentration (g/m3)220Ozone yield (kWh/kg−03)11Discharge power density (W/cm2)0.3Discharge power (kW)452Ozone generation rate (kg/h)41.11Gas flow rate (L/min)3806.1Operating frequency (kHz)1Load power factor (%)30Load current (A)150.72Load voltage (kV)10
The relationship between the discharge load resistance and the ozone capacity of the ozone generator is as indicated in a characteristics diagram in FIG. 13. In FIG. 13, characteristic E represents the characteristic of the cylindrical multi-pipe ozone generator that operates on a conventional AC voltage having a frequency of 1 kHz. The discharge resistance characteristic is as indicated by 8001a. The larger the capacity is, the smaller the discharge resistance (load impedance) becomes. Therefore, it is difficult to disperse a silent electric discharge over a large discharge area uniformly and steadily.
The relationship between the frequency and the discharge voltage to be applied to the ozone generator is as indicated in a characteristic diagram in FIG. 14. In FIG. 14, characteristic F (solid line) is a discharge voltage characteristic prevailing at a discharge gap length of 0.1 mm and at a discharge power density of 1.5 W/cm2. Characteristic G (dotted line) is a discharge voltage characteristic prevailing at a discharge gap length of 0.3 mm and at a discharge power density of 0.3 W/cm2. The lower the frequency is, the higher the discharge voltage becomes. The higher the discharge power density, the higher the discharge voltage. The conventional cylindrical multi-pipe ozone generator generates ozone at a discharge gap length setting of approximately 0.3 to 0.6 mm, at a frequency setting of 1 kHz to 3 kHz, and at a discharge power density setting of 0.3 W/cm2. Therefore, the operation region in FIG. 14 is 8001b and the discharge voltage is approximately 10 kV. If the discharge power density is higher than 0.3 W/cm2, the discharge voltage increases by more than 12 kV. Therefore, the discharge power density should not be higher than 0.3 W/cm2 from the viewpoint of practical apparatus use.
Further, when a plurality of 40 mm diameter and 2000 mm long cylindrical glass high-voltage pipes 5 are inserted at an operating frequency of 1 kHz and at a discharge power density of 0.3 W/cm2, the cubic capacities of a conventional ozone generator generating ozone at a rate of 7 kg/h and a conventional ozone generator generating ozone at a rate of 70 kg/h are as large as 0.7 m3 and 56 m3, respectively, as indicated by 8003a in FIGS. 15 and 8003b in FIG. 16. Since the power factor of the ozone generator is as low as 30% at an operating frequency of 1 kHz, the discharge capacity is extremely large. Thus, the transformer 2000 and inverter element 4000 are very large. Consequently, the large-capacity ozone generator is a huge system.
Various prior arts were disclosed to technically improve the conventional large-capacity ozone generator.
First of all, a large-capacity ozone generator, which was disclosed by Japanese Patent Application No. 2002-306941 prior to the present invention, includes a chamber. The chamber houses a plurality of discharge cells. The discharge cells have a discharge space having a gap of approximately 0.1 mm. The discharge space is provided between two rectangular flat-plate electrodes and two flat-plate electrodes via a dielectric. In this ozone generator, a plurality of discharge cell electrodes, which are mounted in the chamber, are connected in parallel. A high AC voltage is applied between the electrodes so that a uniform dielectric barrier discharge (silent electric discharge) occurs in the gap section of each discharge cell via the dielectric. At the same time, a material gas based on an oxygen gas is allowed to enter the chamber so that a gas uniformly passes from the outer circumference of a discharge cell to the discharge space having a gap as short as 0.1 mm. Consequently, a large amount of ozone gas is obtained. Further, the operating frequency is set to 10 kHz to reduce the discharge voltage. In addition, a discharge power density of 1.0 W/cm2 is employed for performance improvement.
A silent electric discharge type ozone generator power supply, which was disclosed by Japanese Patent Laid-Open No. 1997-59006 prior to the present invention, includes a plurality of discharge pipes and a transformer. In the transformer, the discharge pipes are arranged and three-phase-connected to a three-phase current type inverter in order to improve the load power factor and ozone generation efficiency.
An ozone generation structure, which was disclosed by Japanese Patents Laid-Open No. 1994-305706 and Laid-Open No. 1995-240268 prior to the present invention, includes an n-phase AC power supply, which generates an n-phase AC output, and n discharge electrode rods, which are positioned in a discharge chamber. One end of each discharge electrode rod is positioned to form an n-sided equilateral polygon. An n-phase AC voltage is applied to the n discharge electrode rods so that a corona discharge occurs near the electrode rods between electrodes. Ozone is then generated by allowing a material gas containing oxygen to flow along the discharge electrode rods, which are arranged to form an n-sided equilateral prism. This polyphase AC multi-electrode corona discharge device exhibits higher efficiency than a single-phase corona discharge device because the former can use a planar discharge between electrodes for ozone generation purposes.
Another ozone generation structure, which was disclosed by Japanese Patent Publication No. 1996-22724 prior to the present invention, includes an n-phase AC output device for generating an n-phase AC output and n discharge electrode rods that are positioned in a discharge chamber. One end of each discharge electrode rod is positioned to form an n-sided equilateral polygon. The other end of each discharge electrode rod is positioned close to a vertex, that is, positioned to form an n-sided equilateral pyramid. An n-phase AC voltage is applied to n discharge electrode rods so that a corona discharge occurs near the electrode rods between electrodes. Ozone is then generated by allowing a material gas containing oxygen to flow from the base section of the discharge electrode rods, which are positioned to form an n-sided equilateral pyramid, to the vertex of the n-sided equilateral pyramid. This polyphase AC multi-electrode corona discharge device exhibits higher efficiency than a single-phase corona discharge device because the former can use a planar discharge between electrodes for ozone generation purposes. This invention is equivalent to the invention disclosed by Japanese Patent Laid-Open No. 1995-240268 although the two inventions differ in electrode rod arrangement.
Another ozone generator, which was disclosed by Japanese Patent Laid-Open No. 1995-157302 prior to the present invention, includes transformers to which a three-phase AC power supply is star-connected (Δ-connected). One end of a secondary terminal of each transformer is connected to a cylindrical terminal as a common electrode. The other end of the secondary terminal is connected to a rod-shaped high-voltage electrode. A high AC voltage is applied to the rod-shaped high-voltage electrode.
In another ozone generator, which was disclosed by Japanese Patent Laid-Open No. 1998-25104 prior to the present invention, discharge cells, which include a plurality of dielectrics and high-voltage electrodes, are multi-layered over a single ground electrode (low-voltage electrode surface). Ozone power supplies, which are based on the combination of a three-phase inverter and a three-phase transformer, and multi-layered discharge cells are divided into three cell groups. A three-phase high AC voltage is applied to the high-voltage electrode section of each cell group. In an alternative embodiment, four ozone power supplies are connected to supply a plurality of high AC voltages to a single discharge chamber. The use of a 3-phase ozone power supply makes it possible to drive three discharge cells and make the power supply section compact and inexpensive.
In another ozone generator, which was disclosed by Japanese Patent Laid-Open No. 2001-26405 prior to the present invention, ozone generator units are stacked. The resulting ozone generator is compact although it has a large capacity.
An ultracompact ozone generator unit 100, which is shown in FIG. 7, was disclosed by Japanese Patent Application No. 2002-306941 prior to the present invention. In FIG. 7, the reference numeral 3 denotes a high-voltage electrode, which is very thin (approximately less than 100 μm in thickness) and sandwiched between thin flat-plate dielectrics 5, which have a thickness of less than 1 mm. The reference numeral 7 denotes a flat-plate electrode, which is a rectangular low-voltage electrode that is 20 mm in width, 500 mm in length, and several millimeters in thickness. A plurality of very thin high-voltage electrodes 3 that are sandwiched between flat-plate dielectrics 5, which are less than 1 mm in thickness, and a plurality of rectangular low-voltage electrodes 7, which are several millimeters in thickness, are stacked alternately to form an ozone generator unit 100, which measures approximately 200 mm by 200 mm and has a length of 500 mm. Two etched flat plates are joined together so that the interior of each rectangular low-voltage electrode 7 is structured to provide a water cooling path and ozone gas acquisition scheme. To form a short gap discharge space, a 0.1 mm protruding spacer is provided on both sides of each rectangular low-voltage electrode 7. To invoke a uniform oxygen gas flow in the rectangular discharge space and improve the ozone generation performance, the employed electrode is devised so as to obtain a plurality of ozone gases from the rectangular discharge space. The water inlet and outlet for electrode cooling and the ozone gas outlet are not shown in FIG. 7. However, the detailed configuration is indicated in Japanese Patent Application NO. 2002-306941.
Japanese Patent Application No. 2002-306941 states that an ultracompact ozone generator 1100, whose capacity is one several-th of the conventional capacity, can be configured, as indicated by 8004a in FIG. 15 or by 8004b in FIG. 16, by mounting a plurality of discharge units 100 in a single discharge chamber as indicated in FIG. 6, raising the power frequency from a conventional level of 3 kHz or lower to approximately 6 to 20 kHz as indicated by 8002b in FIG. 14, and increasing the discharge power density of the ozone generator from a conventional level of 0.3 W/cm2 to approximately 1 to 2 W/cm2.
In the conventional cylindrical multi-pipe ozone generator, the ozone performance characteristic is such that the maximum ozone concentration is approximately 220 g/m3 as indicated by 8005a in FIG. 17. In the multi-layer flat-plate ozone generator, on the other hand, the maximum ozone concentration is 340 g/m3 as indicated by 8005b in FIG. 17. It means that the resulting ozone concentration is 1.5 times higher than the conventional level. As regards the ozone concentration achieved by the large-capacity ozone generator, the electrical energy required for acquiring ozone gas at a rate of 1 kg/h (ozone yield) is more important than the maximum ozone concentration. If greater importance is attached to the ozone yield as indicated in FIG. 17, the ozone concentration is approximately 180 g/m3 during the use of the cylindrical multi-pipe ozone generator and 210 g/m3 during the use of the multi-layer flat-plate ozone generator. It means that the ozone yield is increased by less than 20%.
Table 2 shows the comparison between the conventional cylindrical multi-pipe ozone generator shown in FIG. 11 and the multi-layer flat-plate ozone generator (on which the present invention is based) shown in FIG. 7. The table indicates that the multi-layer flat-plate ozone generator is superior to the conventional cylindrical multi-pipe ozone generator in terms of capacity and compactness. However, the conventional cylindrical multi-pipe ozone generator is superior to the multi-layer flat-plate ozone generator in terms of apparatus simplicity, assembling ease, and production cost. However, Japanese Patent Application No. 2002-306941 states that a rectangular, high-performance, multi-layer flat-plate ozone generator can provide apparatus simplicity and assembling ease. It means that the multi-layer flat-plate ozone generator is also becoming advantageous in terms of capacity.
TABLE 2Cylindrical multi-Multi-layer flat-pipe typeplate typeDischarge cell20 cm × 20 cm × 50 cm20 cm × 20 cm × 50 cmcubic volumeNumber of25 (φ40-500)32 (200 × 5-500)dischargesDischarge1.512.76area (m2)Rated ozone180210concentration(g/m3)Maximum ozone220340concentration(g/m3)Ozone yield119.5(kWh/kg−03)Discharge power0.31.1density (W/cm2)Discharge power4.5230.41(kW)Ozone generation0.413.20rate (kg/h)Gas flow rate38.1254.1(L/min)Operating110frequency(kHz)Voltage (kV)106
In an ozone generator including a short gap discharge device, in which the frequency setting is several kilohertz or higher and the discharge power density is 0.5 W/cm2 or higher, the relationship between the ozone capacity and discharge resistance, which is shown in FIG. 13, indicates that the maximum single unit capacity is limited. In FIG. 13, discharge characteristics A to D at a discharge power density of 1.4 W/cm2 represent the characteristics of the multi-layer flat-plate ozone generator. Discharge characteristic E represents the characteristic of the conventional cylindrical multi-pipe ozone generator and prevails at a frequency of 1 kHz and at a discharge power density of 0.3 W/cm2. As indicated by characteristic region 8002a for the multi-layer flat-plate type, the use of a large-capacity ozone generator remarkably reduces the discharge resistance of the ozone generator and makes it difficult to disperse a discharge over the entire surface and generate stable ozone. As a result, it is found that the use of a large-capacity ozone generator in place of a small-capacity ozone generator cannot obtain high-concentration ozone and reduces the ozone yield. Further, the results of experiments indicate that a discharge resistance of approximately 20 ohms or more is required for increasing the ozone generator capacity in consideration of apparatus controllability and stability. It is therefore found that the maximum single unit capacity of the multi-layer flat-plate ozone generator is approximately 10 kg/h. An increase in the single unit capacity results in a poor discharge power factor and increases the peak current for the load current value. It means that an economical limit is imposed due, for instance, to an increase in the power consumption for ozone generation. Consequently, the single unit capacity of the ozone generator is limited. Furthermore, an increase in the single unit capacity remarkably reduces the discharge cell load impedance. It means that the power supply control capability for stable supply of generated ozone is extremely degraded. As a result, various problems, including the inability to increase the single unit capacity, have arisen.
Meanwhile, an ozone water treatment apparatus, which uses ozone, or an ozone pulp bleaching apparatus, which uses ozone for pulp bleaching, requires several tens to several hundreds of kilograms of ozone per hour. If a several-hundreds-of-kilograms-per-hour class, cylindrical, multi-pipe ozone generator is employed, a large-scale facility having a cubic volume of approximately 200 m3 results due to electrode shape. In the field of water treatment or pulp bleaching, which requires the use of ozone, therefore, an extremely compact apparatus having a single unit capacity as large as several tens of kilograms to 100 kilograms per hour and exhibiting high ozone yield and high ozone concentration is demanded.
To configure an ozone generator having a single unit capacity as large as several tens of kilograms to 100 kilograms per hour, it is found necessary, as described above, not only to employ a chamber configuration that accepts a plurality of discharge cells, but also to review the ozone generator system configuration including an ozone power supply. It is also found necessary that a plurality of ozone power supplies be arranged in an ozone generator unit and rendered electrically independent of each other to control the amount of ozone generation.
Patent Document 1: Japanese Patent Laid-Open No. 1997-59006
Patent Document 2: Japanese Patent Laid-Open No. 1994-305706
Patent Document 3: Japanese Patent Laid-Open No. 1995-240268
Patent Document 4: Japanese Patent Publication No. 1996-22724
Patent Document 5: Japanese Patent Laid-Open No. 1995-157302
Patent Document 6: Japanese Patent Laid-Open No. 1998-25104
Patent Document 7: Japanese Patent Laid-Open No. 2001-26405

Toshiba Mitsubishi-Electric Industrial Systems Corporation


FEC (Forward Error Correction) decoder with dynamic parameters. A novel means by which FEC parameters may be encoded into, and subsequently extracted from, a signal stream to allow for adaptive changing of any 1 or more operational parameters that govern communications across a communication channel. FEC parameters are encoded directly into a data frame such that the data frame is treated identical to all other data frames within the signal stream. When the data frame actually includes FEC parameters, it is characterized as a CP (Control Packet) type. For example, when decoding an MPEG stream, an MPEG block that includes FEC parameters, that MPEG block is characterized as a CP MPEG block. The means by which FEC parameters are encoded and extracted from the signal stream allows for much easier adaptive modification of the manner by which signal are encoded, modulated, and processed within a communication system.

1. Technical Field of the Invention
The invention relates generally to communication systems; and, more particularly, it relates to decoding processing within such communication systems.
2. Description of Related Art
Various communication systems have been under constant development for many years. Within certain types of communication systems, FEC (Forward Error Correction) is employed such that various parameters employed within the receiver end/decoder end of a communication channel are appropriately suited to be able to correct for most (ideally, any) errors that may be introduced within signal transmitted across the communication channel from a transmitter end to a receiver end. Sometimes, it is desirable to adjust certain of the various operational parameters within a receiver end communication device in an effort to compensate for any changes to the operating conditions (or communication device status) thereby providing relatively good performance and error correction.
However, in order to change these operational parameters within an FEC functional block within a receiver end communication device, the parameter configuration should be changed on the fly (i.e., in real time) for adaptive modulation and coding. In order to support this approach to performing FEC decoding, the FEC decoding parameters must be known and programmed to an FEC decoding functional block before input signals get into the FEC block. However, the approaches for doing this within the prior art do not provide for very operation and performance.
One prior art way of adaptively modifying the operational parameters for an FEC block is to send the FEC parameter information in frame headers and to extract the FEC parameters out of them. Once these FEC decoding parameters have been extracted from the frame headers, then those FEC decoding parameters may then be programmed back to the corresponding FEC block. This approach is typically a 1 to 1 approach, in that, a header includes FEC operational parameter information corresponding to an immediately following and subsequent FEC block. This prior art is shown pictorially in the following described prior art figures.
FIG. 1A is a diagram illustrating an embodiment of a prior art frame structure. In this illustration, it can be seen that the frame header immediately preceding an FEC block includes the FEC operational parameters that correspond to the immediately following FEC block. This information immediately extracted from the header is then employed to configure the FEC decoding parameters that are used to perform the FEC decoding of the FEC block immediately following the frame header. This prior art inherently involves an undesirable decoding and operational latency, in that, the header of the FEC block must be processed (to extract the information corresponding to the FEC operational parameters by which the subsequent FEC block is to be decoded), then the FEC block must be configured according to that extracted information, and then the FEC block is then actually decoded. This latency is existent for each and every header and FEC block combination within this prior art approach.
FIG. 1B is a diagram illustrating an embodiment of a prior art receiver architecture that may be employed to effectuate the approach of the corresponding FIG. 1A described above. An input signal is first provided to a demodulator that performs any of the necessary demodulation of the received signal to get it into a format that is appropriate for subsequent FEC decoding. In addition, the output of the demodulator is simultaneously provided to a parameter extraction functional block and to a FEC decoding functional block. The FEC decoding functional block must wait for the extraction of the FEC decoding parameters from the parameter extraction functional block before performing FEC decoding in a manner that is appropriate for the FEC block that immediately follows the frame header from which the FEC decoding parameters have been extracted. Again, it can be seen that this latency with respect to this prior art approach to adjust the FEC operational parameters involves processing the header that includes information corresponding to the FEC operational parameters, configuring the FEC functional block according to the most recently extracted FEC operational parameters, and then performing the actually decoding using the FEC decoding functional block of the corresponding FEC block for which these FEC operational parameters correspond.
Moreover, in this prior art approach, the frame headers are either not protected by any error control code, or they are protected by a different FEC that protects the FEC blocks within the input signal stream. This different FEC that may be employed to protect the frame headers is less powerful than the one for the actual data part of the input signal stream. This type of prior art receiver suffers from many deficiencies.
For example, it cannot operate at low SNR (Signal to Noise Ratio) because the frame headers are vulnerable to noise, as they are typically not protected by any error control code. Also, this prior art approach suffers from the inherently slow and serial approach performed by this prior art receiver architecture that includes a parameter extraction functional block that must be employed before performing any FEC decoding of the FEC blocks of the input signal stream that immediately follow the frame header (e.g., the frame header that includes the FEC decoding parameters for that immediately following FEC block). Also in the prior art, the information pertaining to the FEC parameters is embedded in the header before the FEC, and it uses a different coding than the data part of the input signal stream or no coding at all thereby providing little protection.
As such, it is clear that there is a need in the art for a manner by which FEC operational parameters may be modified and adjusted on the fly (i.e., in real time) to effectuate higher performance within error correctional coding communication systems.


A method for determining telomerase activity using primer extension followed with real time PCR quantification is disclosed. The method of the present invention provides a rapid, sensitive and accurate measurement for telomerase activity in a biological sample. In one embodiment, the method includes the steps of: adding the biological sample to a reaction tube containing a first reaction mixture having a first primer and nucleoside triphosphates, a second reaction mixture having a second primer and a DNA polymerase, and a wax layer that separates the first reaction mixture from the second reaction mixture; incubating the biological sample with the first reaction mixture; admixing the extension product with the second reaction mixture; amplifying and quantifying the extension product using real-time PCR and a control template. In another embodiment, the detection method includes an in situ primer extension step that allows the production of the extension product within an intact cell. In this embodiment, the extension product can be preserved under appropriate conditions for an extended time before the completion of the quantification step.

Telomerase is an enzyme that synthesizes telomeres on chromosome ends. Telomeres are DNA sequences found at the ends of eukaryotic chromosomes which maintain the fidelity of genetic information during replication. Under normal circumstances, telomeres become shorter and shorter with each cycle of cell division. A sufficiently short telomere is believed to signal the cells to stop dividing.
Telomerase belongs to a class of enzymes known as reverse transcriptases that use RNA as a template for creating DNA. Telomerase contains both RNA and protein components. The RNA portion of the enzyme binds to the DNA in the telomere while the protein component lures DNA subunits into the region and attaches them to the end of the chromosome. Telomerase then elongates the G-rich strand of chromosomal termini by adding telomeric repeats. This elongation occurs by reverse transcription of a part of the telomerase RNA component, which contains a sequence complementary to the telomere repeat. Following telomerase-catalyzed extension of the G-rich strand, the complementary DNA strand of the telomere is presumably replicated by more conventional means. In the case of eukaryotic organisms, telomerases are composed of an accumulation of repeated defined nucleotide sequences (repeats) which, for example, contain the sequence TTAGGG in humans.
Telomerase activity is not detectable in normal tissues except germline cells. Germline cells, whose chromosomal ends must be maintained through repeated rounds of DNA replication, do not decrease their telomere length with time, presumably due to the activity of telomerase. Stem cells of renewing tissues express very low levels of telomerase and their telomeres shorten with multiple cell divisions. Telomerase activity is occasionally detected in tissues adjacent to tumors possibly reflecting the presence of occult micrometastases.
Telomerase is believed to have a role in the process of cell senescence. The repression of telomerase activity in somatic cells is likely to be important in controlling the number of times they divide. Indeed, the length of telomeres in primary fibroblasts correlates well with the number of divisions these cells can undergo before they senescence. The loss of telomeric DNA may signal to the cell the end of its replicative potential, as part of an overall mechanism by which multicellular organisms limit the proliferation of their cells.
Due to its role in controlling replication, telomerase has also recently been implicated in oncogenesis. Telomerase activity has been detected in most tumor cells. It has been suggested that telomerase is responsible for the unchecked growth of human cancer cells. Unlike normal cells, in cancer cells telomerase appears to grant the cell immortality by maintaining telomere length so that the cell never receives a signal to stop dividing. The telomerase enzyme is an ideal target for chemotherapy because this enzyme is active in about 90 percent of human tumors, but inactive in most normal cells. Pharmaceutical companies have screened thousands of compounds to find agents capable of blocking telomerase.
A method termed as telomeric repeat amplification protocol (TRAP) has been developed to measure telomerase activity. TRAP is based on the in vitro detection of the enzyme activity. Briefly, a synthetic oligonucleotide derived from the telomere sequence is used as a substrate. This substrate is elongated by the telomerase in a test sample and the elongation product is then amplified and quantified. Detailed description of the TRAP methods can be found in, for example, U.S. Pat. No. 5,891,639 to Harley et al. (hereinafter Harley) and U.S. Pat. No. 6,221,584 to Emrich et al. (hereinafter Emrich). Recently, a number of research groups have reported modified TRAP methods using real-time polymerase chain reaction (PCR) technology (See e.g., Hou et al., Clin. Chem. 47:519-524, 2001; Elmore et al., Diagn. Mol. Pathol., 11,177-185, 2002; and Wege et al., Nucleic Acids Res., 31:E3-3, 2003). Specifically, real-time PCR technology has been employed to provide a faster and more sensitive quantification of the elongation product of telomerase.
The current TRAPs typically include multiple incubation steps and transfer of sample from one tube to another after each incubation step. The transferring process is time consuming and prone to contamination and operation error (e.g., adding samples to a wrong tube or well). The current TRAPs usually start with a cell or tissue extract. Since telomerases, which contain both RNA and protein components, are subjected to the digestion of proteases and RNases in the extract, protease inhibitors and/or RNase inhibitors are often needed to prevent the degradation of the telomerases. Addition of protease inhibitors and/or RNase inhibitors to the extract increase the cost of the analysis. Thus, a need exists for an telomerase assay that is more flexible and can be performed easily and quickly at a low cost.

Methods and compositions for detecting telomerase activity


A control system for a cutting reel unit includes a height-of-cut adjusting system and a reel-to-bedknife clearance adjusting system. The height-of-cut adjusting system includes a first frame; a second frame; a cutting reel supported by the second frame; a bedknife arranged adjacent to the cutting reel and supported by the second frame; at least one support element arranged to translate along the ground and arranged to support the first frame; and at least one first actuator connected between the first frame and the second frame and arranged to adjust the relative elevation of the second frame with respect to the first frame. The reel-to-bedknife clearance adjusting system includes at least one second actuator operatively connected between the reel and the second frame and a sound detector.

Conventional mowing machines have an attached cutting reel unit or multiple units. Such machines typically move the cutting reel unit across the ground adjacent to the machine. Grass beneath the cutting reel unit is mowed as the machine travels forward. Conventional reel mower vehicles can include a plurality of arm members that extend from the vehicle, each arm having a cutting reel unit attached to its outer end portion.
The cutting reel units typically include front and rear skids or rollers that support or carry the cutting reel unit across the surface of the ground during mowing operation. Such vehicles and cutting reel units are disclosed for example in U.S. Pat. Nos. 5,343,680; 5,412,931 and 5,459,984.
Conventional cutting reel units provide a plurality of blades coupled together to form a generally cylindrical reel that rotates about a transverse axis. The blades pass in close proximity to a bedknife to create a scissoring action for cutting vegetation such as grass. A frame typically houses the reel and bedknife. Wheels, rollers or skids are coupled to the frame for engaging or rolling across the ground to operatively support the reel and bedknife at a predetermined height above the ground. The height at which grass is cut is therefore determined by the height at which the wheels, rollers or skids carry a frame, reel and bedknife above the ground. Cutting reel units are typically used for mowing golf courses or other areas were a relatively low and accurate cut is desirable.
To produce a high quality cut, and a cut that is even for multiple cutting reel units and across mowing passes by a machine with multiple cutting reel units, it is necessary that the height-of-cut for each cutting reel unit be properly adjusted. It is known that reel mowers have an adjustment mechanism for adjusting the reel mowing height. One type of height adjustment mechanism utilizes a plurality of vertically aligned holes for a cutting unit frame. The rollers are coupled to a mounting member or plate that includes an opening. The mounting plate is coupled to the frame by insertion of a pin through both the mounting plate opening and one of the holes defined by the cutting unit frame. The cutting height can be varied by inserting the pin through a different hole in the frame. Other types of height adjustment mechanisms utilize threaded bolts which set the adjustment height using nuts engaged on the bolts and positionable to support a portion of the frame such that the cutting reel unit is held securely in the desired vertical position with respect to the rollers. A wrench is used to adjust the nuts to positions on the bolts to thereby adjust the cutting height.
Another type of cutting reel unit utilizes a slotted mounting arm that is coupled with the rollers. A bolt received by the slot is used to adjust the height by loosening the bolt and shifting the slide-mounting arm to a new position.
For all height-of-cut adjustments, there is a generally accepted and common method for determining a cutting reel unit's existing height-of-cut and how far it needs to be adjusted towards a targeted adjustment. The procedure for setting the cutting height typically involves fastening a gauge bar to the bedknife such that the upper surface of the bar is parallel to a forward, horizontal position of the bedknife and at the desired distance below the cutting edge of the bedknife. The front and rear rollers are then adjusted to come into contact with the upper surface of the gauge bar.
The adjustment relationship between the front and rear rollers—relative to the cutting reel itself—is often termed the 'angle of attack' for the bedknife. This relationship refers to the relative pitch (front to back) or angle of the bedknife in relation to the ground surface. The angle of bedknife attack is an important parameter which affects the cut quality and effectiveness. Varying the height-of-cut must take the angle of attack into consideration.
Cutting reel units cut properly only if the reel-to-bedknife clearance is properly adjusted. Currently, the reel-to-bedknife clearance is manually adjusted. The adjustment is made on a regular basis, typically before use, or made during or after use when poor cut quality is detected. Sometimes the adjustment is made such that the reel touches the bedknife and then the reel and bedknife are allowed to wear into place. Adjustments are also made after repair or replacement of the reel or bedknife.
Specifically, the reel-to-bedknife clearance is adjusted by moving the reel away from the bedknife to allow a specific gap—that is even across the length of the reel and bedknife—between both the reel and bedknife. The gap is then measured by inserting a feeler gauge (of the same thickness as the adjustment gap) between the reel and bedknife. The adjusted gap between the reel and bedknife is determined to be accurate when the feeler gauge can be moved smoothly between the reel and bedknife across the entire length of the reel and bedknife, such that there is only a slight drag of the feeler gauge as it is moved across this length. To verify reel and bedknife sharpness and a correct reel-to-bedknife adjustment, a single strip of paper is often inserted between the reel blade and bedknife while the reel is turned forward by hand. If the reel cuts the paper, the sharpness and adjustment are usually determined to be correct. The quality of the cut of the piece of paper across the single sheet can be examined to indicate whether the clearance is correct.
Reel adjustments are also necessary when a cutting reel unit is "re-tasked," in effect, adjusted for cutting another type of grass or grass to be cut to a different height. For example, a cutting reel unit could be re-tasked from an adjustment appropriate for a golf course fairway to adjustment appropriate for a golf course green, the two areas having different grass height requirements. However, re-tasking a cutting reel unit is time-consuming. To avoid re-tasking cutting reel unit, many golf courses have cutting reel units or cutting machines which remain designated or pre-adjusted for particular grass requirements, in effect, a designated group of cuffing units for different areas of the golf course. This technique necessitates multiple cutting units or cutting machines. Multiple cutting units or machines can result in higher capital costs and maintenance costs.
The present inventors have recognized that the cut quality of a reel mower is largely determined by the accuracy and precision of adjustment of several key factors. The present inventors have recognized that proper mower adjustments are often hard to achieve through manual adjustment methods.
The present inventors have recognized that the reel-to-bedknife adjustment is one such adjustment that needs to be adjusted accurately and precisely, but is often hard to achieve on individual mowing reels. The present inventors have recognized that the reel height-of-cut adjustment is another such adjustment that needs to be adjusted accurately and precisely, but is also difficult to adjust on individual mowing reels.
The present inventors have recognized that the accuracy and precision of these adjustments can be improved through automated adjustments.
The present inventors have recognized that a need exists for dynamic adjustment capability for multi-area mowers or mowers that are capable of mowing multiple areas having different cutting requirements. The present inventors recognize that a need exists to be able to re-task a cutting reel unit dynamically to allow a single machine to mow multiple area types with different cutting reel unit setup requirements.
The present inventors have recognized the need to also modulate reel speed, to provide reel-to-bedknife contact detection, and to make cutting reel unit adjustments during operation of the cutting reel unit.
The present inventors have recognized the need to improve the adjustment process to ensure a shorter required time, ease of adjustment, and improved reel operation quality.

This patent is subject to a terminal disclaimer.


In one embodiment, a state-varying hybrid stream cipher operating within a computing device. The state-varying hybrid stream cipher comprises at least two software routines. A first routine is responsible for dividing incoming plain text into variable-sized blocks. A second software routine is for converting the plain text into cipher text based on an encryption key, an internal identifier and perhaps a percentage of random data value.

As communications over public networks evolve, secure data communications between different computing devices have become increasingly important. Without security, any interloper can obtain access to data being transmitted. With security, however, the data can be protected from unauthorized access. In order to accomplish secure data communications, various encryption/decryption functions have been developed.
In general, there are two common types of encryption/decryption schemes. The first scheme involves symmetric cryptography while the second scheme involves asymmetric cryptography. For asymmetric cryptography, a key pair is utilized in which one key is used for encryption and the other key is used for decryption. However, computations involving asymmetric cryptographic algorithms are complex, which contributes to greater processing time and slower overall system performance. In contrast, symmetric cryptographic ciphers (referred to as "ciphers") utilize a single key for encryption and decryption operations. As a result, ciphers generally perform computations (e.g., encryption or decryption) faster than asymmetric cryptographic functions.
Normally, there are two types of ciphers, namely a stream cipher and a block cipher. One form of stream cipher, named "RC4," was developed by RSA Data Security, Inc. of Bedford, Mass. However, RC4 and other conventional stream ciphers suffer from a number of disadvantages. For example, RC4 is vulnerable to an attack if a portion of the plain text (original data) and its corresponding cipher text are known. The reason is that a pseudo-random data stream produced by a RC4 cryptographic engine is exclusively OR'ed with the plain text in order to produce the cipher text. Thus, the existence of an identifiable correlation between plain text and cipher text exposes the data produced from the stream cipher to cryptographic attack.
Another disadvantage is that the initial byte of the pseudo-random data stream generated by RC4 is correlated to bytes of the key. In effect, this correlation also exposes the data produced by RC4 to cryptographic attack.
A common feature of encryption is that a plain text maps uniquely to a cipher text for a known encryption key. Thus, if the same plain text is encrypted at a different time with the same encryption key, the same cipher text is generated. This allows an interloper to investigate any correlation between cipher text and plain text in efforts to predict further communications.
Thus, it would be very desirous to have a cipher that overcomes these and other disadvantages associated with RC4 and stream ciphers, and generate different cipher text sequences for the same plain text and a given key, and have all the different cipher text sequences decrypt to the plain text with the same key.


The present invention relates to an emission control system for reducing gases from the exhaust of a combustion engine. In at least one embodiment, the emission control system includes an exhaust passage for transporting the exhaust from the combustion engine, and a particulate filter and selective catalytic reduction (SCR/PF) unit disposed within the passage, with the unit having a plurality of spaced filter walls extending axially along the passage and selective catalytic reduction catalyst variably loaded on the unit to provide a more uniform pressure drop relative to a unit having uniformly loaded catalyst.

1. Technical Field
One or more of the embodiments of the present invention relate to an emission control system for removal of regulated combustion components from the exhaust of a combustion process, such as an internal combustion engine.
2. Background Art
Exhaust from a combustion engine typically contains a variety of combustion components or gases such as unburned hydrocarbon (HC), carbon monoxide (CO), particulate matter (PM), nitric oxide (NO), and nitrogen dioxide (NO2), with NO and NO2, collectively referred to as nitrogen oxide or NOx.
Conventional emission control systems often use separate devices for the reduction of NOx or particulate matter. For example, in one conventional such system, a singular SCR (selective catalytic reduction) catalyst is used for converting NOx to nitrogen (N2) and a singular particulate filter (PF) is used for removing particulate matter. In this situation, the singular SCR catalyst and the singular particulate filter can be sequentially aligned and disposed separable from each other.
In at least situations where space conservation may be a consideration, a combined singular SCR catalyst on a particulate filter unit (SCR/PF) has been explored. In these instances, the pore size of the particulate filter is generally increased and the SCR washcoat is applied onto the filter and into the pores. One problem that has been observed with SCR/PFs is that the backpressure of the filter unit significantly increases as a result of the SCR material disposed in the filter pores. Also, since the SCR/PF is wall-flow technology, the gas passes through the SCR/PF in a non-uniform manner, with the majority of the gas typically flowing through axial center of the filter substrate. This contributes to the high pressure drop observed with SCR/PF use (since much of the gas is going through a relatively small portion of the filter) and decreases the overall effectiveness of the SCR for NOx reduction (since a relatively small percentage of the SCR material is being exposed to the exhaust gas).
There is thus a continuing need to provide an emission control system with a relatively small space consumption and/or a relatively high NOx reduction efficiency while minimizing system complexity.

Progressive catalyst loading for integrated particulate filter and selective catalytic reduction unit


In a planar gyrator, parallel transmission lines are positioned proximal to a magnetized gyrotropic substrate. Input and output transducers couple the ends of the transmission lines to corresponding input and output ports. The input and output transducers are configured to excite first and second partial wave fields on the transmission lines of similar or different phases respectively. The wave fields, in turn, interact gyromagnetically with the substrate, such that the resultant difference in phase change for a first wave propagating from the first to the second port and a second wave propagating from the second to the first port is an odd-integer multiple of 180 degrees. Alternatively, if the magnetization of the substrate is reversed, the phase of a wave propagating from the first to the second port is changed by 180 degrees. The planar gyrator is amenable to application in miniaturized planar microwave devices, for example as a magnetically-controlled phaser or switch, or as a component in a circulator or isolator implemented in planar microwave technology.

The term gyrator was introduced by Tellegen to designate the concept of a circuit element embodying the essence of nonreciprocity:
1. B. D. H. Tellegen: "The Gyrator, a New Electric Network Element"; Philips Res. Rep. 3, 81-101 (1948). PA1 2. C. L. Hogan: "The Microwave Gyrator"; The Bell System Technical Journal, Vol. XXXI, No. 1, 1-31 (January 1952). PA1 3. F. Bloch, W. W. Hansen & M. Packard: "The Nuclear Induction Experiment"; Phys. Rev. 70 474 (1946). PA1 4. N. F. Ramsey, Nuclear Moments; Wiley, 1953. PA1 5. C. L. Hogan, "The Ferromagnetic Faraday Effect at Microwave Frequencies and its Applications" Rev. Mod. Phys., Vol 25, pg 253 (1953). PA1 6. B. Lax & K. J. Button, Microwave Ferrites and Ferrimagnetics; McGraw-Hill, Sec. 12-1, p. 544 (1962).
Thus, where every reciprocal linear circuit device can be represented by an appropriate combination of the four basic element types, inductor, capacitor, resistor, and ideal transformer, Tellegen envisioned that by augmenting these with a fifth element type, the gyrator, every non-reciprocal linear device could be represented as well.
The gyrator is a non-dissipative two-terminal device having forward and reverse transfer phases which differ by 180.degree..
This property might seem to violate the reciprocity principle, a consequence of the symmetry properties with respect to time of the fundamental laws of electromagnetism as expressed by Maxwell's equations, which state that if a voltage is introduced at a first location in a network, and a current is measured at a second location, then the voltage/current ratio will be the same if the locations of the voltage source and current sensor are interchanged.
In fact, the gyrator represents no violation of this general principle at all, but is instead a manifestation, under appropriate conditions, of the distinctive constitutive properties of certain media of electromagnetic propagation, called gyrotropic, which are capable of undergoing a change in their influence on propagating electromagnetic waves under reversal of their state of magnetization. Magnetized ferrites and related magnetic oxides such as YIG (yttrium-iron garnet), magnetoplumbites, and gaseous and solid-state plasmas are examples of gyrotropic materials. Thus, the conventional term "nonreciprocal" should not be taken literally, but only as a convenient designation for this class of phenomena. This property is exhibited with particular clarity in the phenomenon of magnetic resonance induction:
and in microwave Faraday rotation of the polarization:
The Bloch and Ramsey references 3,4 !illustrate magnetic resonance induction at radio frequencies. In these examples, a sphere or other small specimen of gyrotropic material is placed at the center of two mutually orthogonal concentric wire loops or coils mounted in an electromagnet. When excited by an applied radio-frequency signal in one of the coils, the magnetic moment of the specimen is set into precessional motion, inducing an output signal in the other coil. The sense of precession, clockwise or counterclockwise, in response to an oscillating signal is related to the direction of the static magnetizing field. If the static field is reversed, the direction of magnetization and the sense of precession reverse. This, in turn, reverses the phase of the electromagnetic coupling. Likewise, if the roles of input and output connections are interchanged, the direction of the magnetic field being left unchanged, the phase relation between the incident and output signal is reversed. This is the physical basis for the gyrator action.
The principle is the same in the case of the Hogan and Lax & Button references 5,6!, which illustrate microwave Faraday rotation. In these examples, a rod of gyrotropic material is mounted on the axis of a circular-cylindrical waveguide and magnetized axially. An incident linearly polarized microwave signal undergoes rotation of its plane of polarization due to interaction with the precessional magnetic motion which the signal induces in the rod. Here again, the sense of polarization rotation is determined by that of the precession which, in turn, depends on the direction of magnetization. To demonstrate the performance of the microwave gyrator, single-mode waveguides connected at the input and output ends of the cylindrical guide are oriented about their axes as polarizer and analyzer to accept polarizations at 90.degree. relative to one another. Similarly, conditions in the rotator section, principally the diameter and composition of the rod, and magnitude of the applied static magnetic field, are arranged to produce a Faraday rotation angle of 90.degree.. Thus, a signal incident from either end undergoes Faraday rotation so as to be suitably polarized for transmission at the other end with only incidental scattering, but the phase of the transmission is opposite (differing by 180.degree.) in the case of the two directions. Likewise, the phase changes for transmission in the two directions are interchanged if the direction of magnetization is reversed. These are the essential characteristics of the gyrator.
The gyrator has long been a focal point of interest in relation to microwave device and system technology, for its practical utility as well as for its theoretical significance. Gyrators have served as the basic nonreciprocal element in circulators and isolators, which are indispensable in microwave systems of all kinds as means to divide, combine and direct signals and to suppress unwanted reflections in microwave systems. Actual physical embodiments of the gyrator can perform as the non-reciprocal element in many magnetic microwave devices; in addition, the gyrator also serves as a powerful abstract concept for logical representation and analysis in microwave circuit theory. Gyrators are also incorporated into devices which provide other essential circuit functions, such as magnetically controlled switching and phase shifting operations.
Prior Art FIG. 1 illustrates a gyrator employed in a four-port circulator which can function as a signal director, divider or combiner or as an isolator or switch. The circuit is a bridge configuration consisting of two "hybrid" or "magic" T junctions, T1 and T2, connected by two parallel lengths of transmission line 22A, 22B. Each junction T1, T2 includes an even symmetry port (circulator ports 1 and 2) and an odd symmetry port (circulator ports 3 and 4). Consider first an incident signal entering the circulator via port 1. The incident signal 20 is divided into two parts 20A, 20B which are conducted on two lines, or arms, of the bridge 22A, 22B. In junction T2, the two signals 20A, 20B are recombined into signal 24. A gyrator G is positioned in the first arm 22A. The lengths of the two arms 22A, 22B are designed such that, for an incident signal entering port 1, the even-symmetry port of T1, and propagating in the direction from T1 to T2, the two signals 20A, 20B remain in phase and are combined to emerge 24 at the even-symmetry port of T2 (circulator port 2).
Consider now a second signal 26 incident on port 2 traversing through the circuit in the opposite direction from junction T2 to T1. Since the gyrator G furnishes a 180.degree. difference in phase for this signal compared with the first direction of propagation, it follows that, for a signal 26 incident at port 2 and divided with equal phase into signals 26A, 26B, the two signals 26A, 26B arrive at T1 precisely out of phase and are combined into signal 28 at the odd-symmetry port (circulator port 3) of T1 . This illustrates the essential circulator action. Continuing the same logic, a signal 30 incident at port 3 of T1 is divided with an initial 180.degree. phase difference at junction T1 due to the odd symmetry at that port and emerges at the odd-symmetry port of T2 (circulator port 4) as signal 32. Likewise, a signal 34 incident on port 4 and divided with an initial 180.degree. phase difference at T2 is affected by a further 180.degree. phase change due to the gyrator G and emerges at the even-symmetry port of T1 (circulator port 1) as signal 36.
The device described in the above example can be adapted for use as an isolator by designating three ports of each T-junction for the signal path, with the remaining port of each T-junction terminated with matched attenuators. This circuit can also serve as a switch or reversible circulator, by taking advantage of the magnetic-control feature intrinsic to the gyrator: if the direction of magnetization of the gyrotropic element is reversed, the gyrator action is reversed and the 180.degree. phase difference between the two arms of the bridge occurs for propagation in the opposite direction, from T1 and T2, thereby reversing the circulation port sequence outlined above, from 1-2-3-4-1 . . . to 1-4-3-2-1 . . . .
Modern implementations of the gyrator generally require a complicated structure, including a magnetic yoke external to the microwave path, which makes them comparatively large in size and weight and expensive to manufacture. For these reasons, modern gyrators do not lend themselves well to the evolving technology of microwave planar circuits, where minimization of size, weight, and cost are essential.


A computing element for use in an array in a neural network. Each computing element has K (K>1) input signal terminals, K input backpropagated signal terminals, K output backpropagated signal terminals and at least one output terminal. The input terminals of the computing element located in row i, column j of the array of computing elements receive a sequence of concurrent input signals on K parallel input lines representing a parallel input signal S.sub.ij having vector elements (s.sub.ij1, s.sub.ij2, s.sub.ij3, . . . , s.sub.ijk).sup.T. The K input backpropagated signal terminals are coupled to receive an m-dimensional (m<K) backpropagated signal vector characterized to provide a measure of the performance error of the computing element. The computing element comprises a weighting function means responsive to the concurrent input signal S.sub.ij for computing a K-dimensional weighting coefficient and a scalar activation signal u.sub.ij by computing a K-dimensional weighting-coefficient vector, W.sub.ij =(w.sub.ij1, w.sub.ij2, . . . , w.sub.ijk).sup.T, and by forming the vector inner product of the input signal S.sub.ij vector elements and the weighting-coefficient vector, W.sub.ij. Feedback signals x.sub.ijk =w.sub.ijk *p.sub.ij are provided from the output backpropagated signal terminals where p.sub.ij provides a performance error of all columns of computing elements subsequent to this computing element weighted by the gain of the computing element. A nonlinear processor maps successive values of u.sub.ij through a nonlinear mapping function, M.sub.ij to provide a single-valued output signal y.sub.ij. The nonlinear processor responds to an m-dimensional backpropagated signal vector, X.sub.ij+1 =(x.sub.1,j+1,p ; x.sub.2,j+1,p ; x.sub.3,j+1,p ; . . . x.sub.m,j+1,p).sup.T characterized to provide a measure of the performance error of all computing elements subsequent to the computing element. Vector X.sub.i,j+1 comprises the pth member of all backpropagated error vectors from the computing elements of column j+1.

1. Field of the Invention
The present invention relates to adaptive signal processors for signal classification, identification and enhancement.
2. Prior Art
U.S. Pat. No. 4,315,319, "Nonlinear Signal Processor" by inventors Stanley A. White and V. A. Vitols, issued Feb. 9, 1982 is of interest because it describes a nonlinear signal-processing technique to combat the problem of nonlinear distortion by mapping an input signal having any given amplitude-density function into a new signal with any given amplitude-density function, subject only to the constraint that the distorting mechanism be a single-valued nonlinear function, the slope of which is everywhere positive. The nonlinear signal-processing technique of that patent has been successfully applied to both speech and image-restoration problems.
U.S. Pat. No. 4,843,583 for "A Non-linear Adaptive Filter" filed Oct. 15, 1985, having a common inventor and assignee is of interest because it depicts an adaptive computation which is used in this invention.


A digital processor-based remote controller of a wireless remote control system includes a small number of manual input devices, such as keys and scroll wheels, and a graphical user interface. The remote controller can have a single scroll wheel with internal push-to-activate switch, and a small display. This configuration minimizes the size of the remote controller, while allowing for a large number of different control commands to be transmitted to the controlled system. In addition, the remote controller can be configured by the user for both right- and left-handed operation.

1. Field of the Invention
The present invention relates generally to remote control systems (RC Systems or simply RCS's), and, more particularly, to remote control transmitters and transceivers (RCTs).
2. Background
Remote controls are widely used to operate television sets, videocassette recorders, digital video players, radios, compact discs, audio tape players, and many other audio and video components and systems. Remote control systems have also been used for decades to control many devices beyond the standard fare of entertainment systems. For example, remote control systems can be used to operate model airplanes, railroad locomotives, boats, cars, and other toys. Remote controls can also be used to exercise functions of security systems, including vehicle and home security systems. Many other remote control applications can be thought of, including control of generators and smart homes. In general, a remote control system includes a remote controller, or simply a remote control, and a device controlled or operated by the remote control. Thus, a remote control is a device or implement through which the operation of one or more systems can be controlled by transmission of control information. It is a device for controlling the operation of the system or systems, as distinguished from a device used solely for transmitting authentication or transaction selection and authorization data.
More often than not, remote control systems are wireless systems. By "wireless" we mean that no direct mechanical connection needs to exist between a controlled apparatus and its corresponding remote control, to transmit control commands between them; instead, the remote control transmits the commands over a wireless link. The wireless link can be an ultrasound link, with the controller transmitting ultrasound signals from an ultrasound transducer to the controlled system. The link can also be a radio frequency (RF) link, including a link implemented over a microwave frequency band, or an infrared (IR) link. These are only some of the more common wireless links, and we do not exclude any other electromagnetic or sound frequencies from the scope of the word wireless in the present context.
With the progress of electronic industry over the years, the capabilities of remote controls have increased substantially. For example, many of the early RF remote control transmitters used only the operating frequency and time (duration) of transmission to operate their controlled systems. Today, there are frequency hopping and direct sequence spread spectrum remote control transmitters with code hopping or code rolling capabilities. Sophisticated encryption algorithms are sometimes used for transmissions over control links, making it difficult to duplicate a particular remote control transmitter without knowledge of its operating scheme. In sum, the technological field of remote controls has grown and advanced with the rest of electronic technologies.
Some of these technological advances have enabled miniature and relatively inexpensive electronic circuitry within a transmitter to operate many more functions of the controlled system than could be operated in the past. These developments have not gone unnoticed by product designers: the trend is to have more and more switches and keys on a remote control, to operate the increasingly sophisticated remotely controlled systems. One example of this trend is the availability of the so-called universal remote control—a remote control that can be manually programmed to learn the operational codes and provide remote control operation of many different entertainment devices.
The size of a typical remote control transmitter for operating a television set or similar entertainment device is about the size of a typical calculator: it can be held in one hand. The number of keys on the face of the typical remote control is perhaps somewhere between one and three dozen. As noted above, the number of available control functions continues to grow. At the same time, manufacturers would like to contain the size of the remote control within the same "hand-held" limits. Because the size of a finger-operated key cannot be decreased much below the size of an average fingertip, the number of keys also needs to be limited.
In other applications, the size of the remote control is even more restricted. For example, a remote control for an automotive security system has to be carried by the driver. Often, the driver carries the remote control on a key chain, either in a pocket or purse. The remote control, the key chain with a few keys, and possibly a wallet or pocket change are expected to fit comfortably in a garment pocket. A remote controller with a multitude of finger-operated keys hardly fits this requirement.
For these and other reasons, the proliferation in the number of keys on the faces of remote controls is unwelcome. Several attempts have been made to reduce this number. For example, some television and other remote controls show the controlled function on the screen of the controlled system. In case of videocassette recorders and similar video devices other than television sets, the function is displayed on the attached television set. The user of the remote control selects the function by depressing the keys of the remote control, or by manipulating a pointing device, for example, a scrolling device built into the remote control. Such remote controls, however, presuppose the availability of a television set or monitor within the operator's viewing range. The range and applications of these devices are therefore limited.
According to a different technique, one key of a remote control is depressed multiple times to select a function with or without a visual or audible indicator, such as an LED or multiple LEDs (number of flashes or color) or a signal chirp, and another key is used to transmit the selected function command. In a variation of this technique, depressing the first key selects the function of the controlled system by selecting the channel or data word to be transmitted, and depressing the second key transmits the selected function command, with the function of each key being determined by the order in which the keys are depressed. As can be easily seen, these solutions still limit the total number of functions accessible from a small number of keys. Moreover, a user's selection of a particular function is made more difficult, because of the complicated sequence in which the keys must be depressed.
In another variation of the technique discussed in the preceding paragraph, one key is used to select a function by holding the key depressed until the desired transmitter channel or control data word is selected, and the remote control transmits the appropriate function selection command when the key is released. Here, however, the user is inconvenienced by the need to observe the LED flashes or color and flashes.
In accordance with another approach, a remote control transmitter uses a keypad with an optional display screen to select desired commands. The keypad is used in conjunction with the screen, in what amounts to a one-to-one correspondence between each of the multiple keys and multiple images (icons) on the screen. The screen can be a touch-sensitive screen, eliminating the need for a separate keypad. But the number of keys, whether being part of the keypad or part of the touch-sensitive screen, remains about the same as the number of functions controlled by the transmitter. Without the screen, the keys on the keypad control separate transmitter control channels or data words that control the functions of the system.
Remote control transmitters for television sets have also been known to incorporate screens for displaying television programming information, possibly including the title of the current program, a movie guide, a sports programming guide, or a children's programming guide. Such use of a display screen, however, does not decrease the number of keys on the remote control transmitter, or the size of the transmitter.
Users of remote controls often prefer to hold and operate the controls with the same hand. Because of the anatomy of the human hand, the finger of choice for pressing the keys is the thumb. Thus, the location of the keys on the face of the remote control is important. Unfortunately, what can be perfect key positioning for a right-handed user, can be a rather inconvenient key positioning for a left-handed user, and vice versa.
Information relevant to attempts to improve remote controls can also be found in U.S. Pat. Nos. 3,944,982; 3,949,297; 3,971,986; 3,988,701; 4,021,756; 4,041,394; 4,746,919; 4,890,108; 4,963,876; 5,038,401; 5,648,781; 5,712,638; 5,774,051; 6,127,941; 6,130,726; and 6,158,655.
Although detailed analyses of the above-described attempts to improve remote controls are beyond the scope of the present document, each suffers from one or more of the following disadvantages: (1) large size of the remote control; (2) large number of activation keys and switches on the remote control; (3) small number of functions accessible through the remote control; (4) difficulty in selecting a desired function through the remote control; (5) lack of adaptability of the remote control to automotive security systems; (6) inability to configure the remote control for both right- and left-handed operation; and (7) inability to program conveniently the remote control in order to customize its operation and appearance.
A need thus exists for remote controllers that can control an increasing number of functions without an accompanying increase in the size of the device or in the number of keys needed to control these functions. A further need exists for miniature remote controllers capable of controlling a large number of functions. Still another need exists for miniature remote controllers that can control a large number of functions of automotive security systems. Yet another need exists for remote controllers that can be configured by the user for both right- and left-handed operation, and to be customized in other respects.


A method for forming a golf club head comprises placing an uncured composite material between a core and a mold that comprises a first piece and a second piece. The second piece is moved towards the first piece such that the uncured composite material is compressed between the core and at least a portion of the mold. The uncured composite material is heated. A first portion of the golf club head is removed from the mold. A second portion of the golf club head is provided. The first portion is attached to the second portion. In certain arrangements, the second portion is formed from a metallic material.

Field of the Invention
The present invention relates to an improved method for producing a golf club head, and more particularly to an improved method of producing a club head made of a carbon fiber composite.
Description of the Related Art
A wood-type golf club typically includes a hollow shaft with a club head attached to the lower end of the shaft. The club head typically includes a load-bearing outer shell with an integral or attached strike plate. The strike plate defines a substantially planar front surface or strike face for striking a golf ball.
A recent trend in the industry is to make the club head out of strong, yet lightweight material, such as, for example, titanium, a titanium alloy or a carbon fiber composite. Of these materials, carbon fiber composites are particularly interesting to golf club designers because it has a density that is roughly one third of the density of titanium but is almost as strong as titanium. Accordingly, carbon fiber composites are particularly suitable for very large club heads (i.e., club heads that define an internal volume greater than 400 centimeters cubed).
Despite their low density and strength, club heads that are made entirely of carbon fiber composites are generally not popular. This is due, in part, to the relatively high stiffness that is typical of carbon fiber composites. Such stiffness usually is undesirable especially in the strike plate. Moreover, carbon fiber composites are not particularly durable. Thus, composite club heads have a tendency to wear out in the areas that are subjected large amounts of wear and friction (e.g., the sole of the club head).
To overcome some of these problems, it has been suggested that the club head be made from a combination of titanium or alloy and carbon fiber composites. Specifically, it has been suggested that a club head can be formed from an outer shell made of a carbon fiber composite, which is attached to a strike plate made of a titanium or a titanium alloy. However, existing methods for manufacturing such a club have not been satisfactory. For example, one golf club manufacturer attempted to co-cure a metal strike plate with a composite outer shell. More specifically, a metal strike plate was placed in a mold along with an inflatable bladder that was surrounded by a uncured composite material. To cure the composite, the bladder was inflated to press the uncured material against the mold and the strike plate. However, fitting the strike face into mold and removing the bladder from the cured club head was difficult and time consuming.

Method for manufacturing and golf club head


Provided is an optical scanning apparatus, including: an optical deflector having a polygon mirror reflecting a light flux emitted from a light source to carry out scanning, a drive unit rotating the polygon mirror about a rotation shaft, and a board supporting the drive unit; an optical box to which the board is fixed; two holes provided in the optical box, through which two screws fixing the board are inserted, respectively; two bearing surfaces provided on the optical box at positions around the two holes, respectively, the two bearing surfaces supporting the board; and an abutment portion provided on the optical box and abutting against a portion that is prevented from being pressed by the two screws in the board which is sandwiched between the two screws and the two bearing surfaces so as to be fixed to the optical box.

Field of the Invention
The present invention relates to an optical scanning apparatus for carrying out optical writing on a photosensitive drum or the like with use of a laser beam and a support member for an optical scanning apparatus in an image forming apparatus such as a laser beam printer (hereinafter referred to as "LBP"), a digital copying machine, and a digital facsimile machine.
Description of the Related Art
Image forming apparatus such as an LBP is configured to form an image on a recording material by forming an electrostatic latent image on a photosensitive drum in accordance with a desired image, developing the electrostatic latent image into a toner image, and by transferring the toner image onto the recording material. To form a desired electrostatic latent image on the photosensitive drum, there is used an optical scanning apparatus for irradiating and scanning the photosensitive drum with a laser beam.
Therefore, the print accuracy of such an image forming apparatus is significantly affected by the mechanical accuracy of the optical scanning apparatus. In particular, in an optical deflector for rotationally driving a rotating polygon mirror, the rotation center of the rotating polygon mirror, which serves as a reference of an optical system of the LBP, needs to be positioned with respect to an optical reference position of an optical box with high accuracy.
In view of the above, there is generally employed such positioning structure that a shaft or bearing of the optical deflector is fitted into a fitting hole provided at the optical reference of the optical box.
Conventionally, an optical deflector including a polygon mirror and a motor unit for rotating the polygon mirror is generally fixed with screws at three points surrounding the motor. In this case, a board is fixed in conformity to bearing surfaces at the respective screw fixing portions. Therefore, when the bearing surfaces are inclined, the board is distorted and the shaft of the motor unit of the optical deflector is inclined.
Further, the inclination of the rotation shaft of the optical deflector, which is called shaft inclination, may cause distortion of a spot-shape of the laser beam on the photosensitive drum, resulting in deterioration in image quality.
According to Japanese Patent Application Laid-Open No. 2005-201941, the optical deflector is fixed to the optical box with use of a screw and a spring, and the screw is tightened and loosened after the optical deflector is fixed, to thereby adjust the push-in amount and control the shaft inclination.
In the structure disclosed in Japanese Patent Application Laid-Open No. 2005-201941, however, the assembly process becomes complicated for the sake of shaft inclination control, thus leading to a problem in that the number of steps is increased.

Optical scanning apparatus, image forming apparatus, and support member for an optical scanning apparatus


The present invention provides systems and methods for creating and editing electronic layouts, such as layouts used to create web pages, via digital networks. An exemplary system for creating an electronic layout suitably includes a server, a network, a database and one or more user interfaces. The server may suitably provide a layout editor configured to place one or more containers, areas and/or spacers onto a layout panel in response to inputs from a user and a layout manager configured to validate properties of the layout and to generate the layout. An exemplary method for creating a document layout suitably includes displaying a layout panel; placing at least one container on the layout panel to create the layout, the container comprising a software object representing a visual element; and storing the layout in a database for future use and/or editing.

With increased use of digital networks such as the Internet, many businesses and other entities have found it beneficial to have their own web sites. Typically, a corporate web site may include multiple pages, for example, for multiple departments within the business, for multiple products or services and the like. In creating such sites, a business often finds it beneficial to maintain a uniform "look and feel," throughout its site, to improve consistency and ease of use. To achieve that uniform look and feel, businesses typically develop guidelines for their employees to follow when developing web pages. These guidelines typically define certain aspects of look and feel, content and procedures for creating and making changes to a web page. One aspect of these guidelines is often directed to the overall layout of given web page. For example, one business may specify that each of its web pages include an identical company banner at the top of the page, similar margins at the sides and bottom of the page, a similar color scheme for the background and lettering on the page and the like.
Due to rapid technological changes and the need to frequently update electronic layouts, guidelines for creating and changing those layouts may themselves change very rapidly as well. For example, in the context of corporate web sites, described above, web site content and format may be updated very frequently. Other examples of electronic layouts provided via digital networks may include any type of electronic layout used on television, electronic message boards, billboards, scoreboard displays, airport displays, cell phones, personal digital assistants ("PDAs"), digital pagers and the like.
In the context of a large corporation, many employees may typically provide or suggest new web page layouts and content for the business. Some of these employees may have limited, if any, knowledge of computer programming and may not understand how to create a web page layout, how to provide their suggestions for a web page in efficient ways or how to achieve the uniform look and feel for a given web page that their business hopes to achieve. The combination, described above, of rapidly changing technology, the desire of businesses to keep their web sites current as well as relatively uniform in appearance, and the input of suggestions for web pages from many different employees may create a drain on an information technology ("IT") department in a large corporation. For example, such a department may spend a large amount of time and resources manually developing new web page layouts and either inputting content into those layouts or creating content that matches those layouts. Some currently available systems, such as the Microsoft Frontpage software, available from Microsoft Corporation of Redmond, Wash., which is hereby incorporated by reference, provide web page creation tools. Current systems, however, do not provide a method for web page layout creation that is accessible by multiple employees in a corporation, via a network, that maintains a uniform look and feel for web pages created within a corporation, and that enables employees with little or no technical background to create, change and enter content into web page layouts.
A need therefore exists for systems and methods for efficiently creating web page layouts within a business setting. A need also exists for systems for creating web page layouts with a uniform look and feel. Ideally, such systems would be accessible by employees of a business via a network and would enable employees with little or no knowledge of computer programming to create and change web page layouts and to use those layouts as templates for creating web pages.

American Express Travel Related Services Company, Inc.


A dummy cell array is provided in a memory cell array, and an intermediate buffer is provided between input/output circuits, whereby control signals to the input/output circuits can be operated at high speed and with a high frequency while the area increasing effect is reduced even in a memory with a large bit width.

The present disclosure relates to techniques of increasing the speed of semiconductor memory devices.
When a memory having a large bit width is operated at high speed, an interconnect resistance, an interconnect capacitance, and a gate capacitance occurring during transmission of a control signal for an input/output circuit, such as a sense amplifier activation signal, a bit line precharge signal, a column decode signal, etc., increases, and therefore, a waveform has more difficulty in increasing or decreasing in further subsequent stages. To address this problem, there is a known technique of supplying a control signal via a repeater to increase the speed (see, for example, Japanese Patent Publication No. H11-353870).
In conventional memories having a typical configuration, an interconnect resistance, an interconnect capacitance, and a gate capacitance occurring during transmission of a control signal for an input/output circuit, such as a sense amplifier activation signal, a bit line precharge signal, a column decode signal, etc., increase with an increase in the bit width, and therefore, it is difficult to increase the speed.
Moreover, when a repeater is employed as in Japanese Patent Publication No. H11-353870, the repeater is provided in a region other than regions in which a sense amplifier or a column decoder is provided and which have a pitch corresponding to that of memory cells. Therefore, memory cells cannot be provided around the repeater, and therefore, a region around the repeater is dead space. The increase in the speed thus leads to an increase in the area.


A memory unit 18 includes a bus 16 which couples the memory unit to a memory control unit 14. The memory unit includes a latch for receiving and storing an address from the bus, a first memory plane for storing information units associated with an odd address, a second memory plane for storing information units associated with an even address, an input latch for receiving from the bus an information unit associated with a received address and output latches for storing, prior to transmission to the bus, a stored information unit associated with a received address. The memory unit further includes logic, responsive to a state of a first bus signal line, for enabling the output latches to (a) simultaneously transmit to the bus an information unit from both the first and the second memory planes, or (b) sequentially transmit to the bus an information unit from one of the memory planes followed by an information unit from the other one of the memory planes.

A memory module for an information processing system typically includes a substrate, such as a printed circuit board, a plurality of memory device integrated circuits, such as dynamic random access memories (DRAMS), and associated logic for generating memory timing and control signals, latching data, etc. One or more of the memory modules are coupled to a system bus of an information processing system and provide storage of data and instructions for one or more central processing units (CPUs) which are also coupled to the system bus. In some systems the memory module(s) may be coupled to the system bus via a memory bus and a memory control unit (MCU), the MCU being interposed between the system bus and the memory bus.
The system bus normally includes a data bus having a predetermined number of signal lines for defining a width of the bus. For example, a data bus may have 8, 16, 32, 64 or more signal lines for conveying an equal number of data bits. Modern, high performance systems are generally characterized by a data bus width of 64 bits (double-word) or 128 bits (quad-word).
The system bus normally also includes an address bus for defining data storage address locations within the memory module(s). The number of signal lines which comprise the address bus is directly related to the number of address storage locations which may be directly addressed by the the bus. For example, 20 address signal lines can directly address approximately one million address locations. Modern systems may have 28 or more address signal lines. For some system bus architectures the address bus is provided as a discrete bus while for other types of systems the address bus is time shared, or multiplexed, with all or a portion of the data bus. For these latter type of systems the multiplexed signal lines can convey an address during a first portion of a system bus cycle and convey data relating to the address during a second portion of the system bus cycle.
The system bus typically also includes a number of control signal lines such as memory read and write strobes, clock and bus cycle timing signal lines, etc.
Conventional practice in the design and manufacture of memory modules is to provide a module suitable for use with only one system bus or memory bus configuration. That is, the memory module is designed to accommodate a fixed data bus width, such as 64 or 128 bits. It can be appreciated that if a manufacturer of information processing systems provides different types of systems having different data bus Widths that a memory module having a fixed bus width would not be useable in two or more different types of systems.
Also, DRAM devices are available in a number of operating configurations including page mode and static column mode. During a conventional page mode access cycle a row address is applied to the device, a row address strobe (RAS*) signal is asserted, a column address is applied and a column address strobe (CAS*) signal is asserted such that a particular address location within the DRAM is selected. The device is repetitively accessed in the page mode by incrementing the column address and reasserting CAS* without incurring the overhead of also changing the row address and reasserting RAS*. Thus, a conventional page mode type of DRAM page mode operation includes repetitive assertions of CAS*.
In a static column type of device the DRAM includes circuitry which detects transitions of the column address signals. With this type of device the requirement of repetitively asserting CAS* is eliminated in that applying a new column address, with CAS* remaining asserted, is sufficient to initiate a device read or write access cycle to the selected address. In general, static column operation results in a faster access cycle in that set-up and hold times associated with CAS* are eliminated.
As can be appreciated, these two types of DRAM devices have differing timing and control signal generation requirements which generally preclude conventional memory modules from operating with both types of devices. That is, conventional memory modules are typically designed to work with one type of device or the other. In that DRAM devices are in great demand and adequate supplies of a given type of device are not always readily available it can be seen that a memory module having the ability to operate with more than one type of DRAM device without modification is a desirable feature.


An exhaust gas cooler for cooling combustion exhaust gas of an internal combustion engine having a cooling medium, wherein the exhaust gas cooler has an exhaust gas inlet for introducing hot combustion exhaust gas into the exhaust gas cooler. Furthermore, the exhaust gas cooler has an exhaust gas outlet for directing cooled combustion exhaust gas out of the exhaust gas cooler, wherein the exhaust gas outlet is fluidically connected to the exhaust gas inlet. Furthermore, the exhaust gas cooler has at least one coolant inlet for fluidically connecting the exhaust gas cooler to at least one coolant outlet of the internal combustion engine. Furthermore, the exhaust gas cooler has an interface for fluidically connecting a water collecting adapter, wherein the interface is designed to carry the coolant out of the exhaust gas cooler.

1. Field of the Invention
The present invention relates to an exhaust gas cooler for cooling combustion exhaust gas of an internal combustion engine with a coolant, to a water collecting adapter for directing coolant out of the exhaust gas cooler, to an exhaust gas cooling system for a multi-cylinder internal combustion engine, and to a method for manufacturing an exhaust gas cooling system.
2. Description of the Background Art
In a conventional exhaust gas cooler for an exhaust gas recirculation in the intake tract of an internal combustion engine, hot combustion exhaust gas is directed out of the internal combustion engine to an exhaust gas cooler in order to be cooled there by ambient air. A coolant can also be used to cool the combustion exhaust gas.
To this end, EP 0 930 429 B1 discloses a device for cooling recirculated exhaust gas of a liquid-cooled internal combustion engine.

Exhaust gas cooler for cooling combustion exhaust gas of an internal combustion engine, water collecting adapter, exhaust gas cooling system and method for manufacturing an exhaust gas cooling system