In one aspect, the present invention provides a systems and methods for the real-time amplification and analysis of a sample of DNA.

1. Field of the Invention
The present invention relates to methods for amplifying nucleic acids in micro-channels. In some embodiments, the present invention relates to methods for performing a real-time polymerase chain reaction (PCR) in a continuous-flow microfluidic system and to methods for monitoring real-time PCR in such systems.
2. Discussion of the Background
The detection of nucleic acids is central to medicine, forensic science, industrial processing, crop and animal breeding, and many other fields. The ability to detect disease conditions (e.g., cancer), infectious organisms (e.g., HIV), genetic lineage, genetic markers, and the like, may facilitate disease diagnosis and prognosis, marker assisted selection, correct identification of crime scene features, the ability to propagate industrial organisms and many other techniques. Determination of the integrity of a nucleic acid of interest can be relevant to the pathology of an infection or cancer.
One of the most powerful and basic technologies to detect small quantities of nucleic acids is to replicate some or all of a nucleic acid sequence many times, and then analyze the amplification products. PCR is perhaps the most well-known of a number of different amplification techniques.
PCR is a powerful technique for amplifying short sections of DNA. With PCR, one can quickly produce millions of copies of DNA starting from a single template DNA molecule. PCR includes a three phase temperature cycle of denaturation of DNA into single strands, annealing of primers to the denatured strands, and extension of the primers by a thermostable DNA polymerase enzyme. This cycle is repeated so that there are enough copies to be detected and analyzed.
In principle, each cycle of PCR could double the number of copies. In practice, the multiplication achieved after each cycle is always less than 2. Furthermore, as PCR cycling continues, the buildup of amplified DNA products eventually ceases as the concentrations of required reactants diminish.
For general details concerning PCR, see Sambrook and Russell, Molecular Cloning—A Laboratory Manual (3rd Ed.), Vols. 1-3, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (2000); Current Protocols in Molecular Biology, F. M. Ausubel et al., eds., Current Protocols, a joint venture between Greene Publishing Associates, Inc. and John Wiley & Sons, Inc., (supplemented through 2005) and PCR Protocols A Guide to Methods and Applications, M. A. Innis et al., eds., Academic Press Inc. San Diego, Calif. (1990).
Real-time PCR refers to a growing set of techniques in which one measures the buildup of amplified DNA products as the reaction progresses, typically once per PCR cycle. Monitoring the accumulation of products over time allows one to determine the efficiency of the reaction, as well as to estimate the initial concentration of DNA template molecules. For general details concerning real-time PCR see Real-Time PCR: An Essential Guide, K. Edwards et al., eds., Horizon Bioscience, Norwich, U.K. (2004).
Several different real-time detection chemistries now exist to indicate the presence of amplified DNA. Most of these depend upon fluorescence indicators that change properties as a result of the PCR process. Among these detection chemistries are DNA binding dyes (such as SYBR® Green) that increase fluorescence efficiency upon binding to double stranded DNA. Other real-time detection chemistries utilize Foerster resonance energy transfer (FRET), a phenomenon by which the fluorescence efficiency of a dye is strongly dependent on its proximity to another light absorbing moiety or quencher. These dyes and quenchers are typically attached to a DNA sequence-specific probe or primer. Among the FRET-based detection chemistries are hydrolysis probes and conformation probes. Hydrolysis probes (such as the TaqMan® probe) use the polymerase enzyme to cleave a reporter dye molecule from a quencher dye molecule attached to an oligonucleotide probe. Conformation probes (such as molecular beacons) utilize a dye attached to an oligonucleotide, whose fluorescence emission changes upon the conformational change of the oligonucleotide hybridizing to the target DNA.
A number of commercial instruments exist that perform real-time PCR. Examples of available instruments include the Applied Biosystems PRISM 7500, the Bio-Rad iCylcer, and the Roche Diagnostics LightCycler 2.0. The sample containers for these instruments are closed tubes which typically require at least a 10 μl volume of sample solution. If the lowest concentrations of template DNA detectable by a particular assay were on the order of one molecule per microliter, the detection limit for available instruments would be on the order of tens of targets per sample tube. Therefore, in order to achieve single molecule sensitivity, it is desirable to test smaller sample volumes, in the range of 1-1000 nl.
More recently, a number of high throughput approaches to performing PCR and other amplification reactions have been developed, e.g., involving amplification reactions in microfluidic devices, as well as methods for detecting and analyzing amplified nucleic acids in or on the devices. Thermal cycling of the sample for amplification is usually accomplished in one of two methods. In the first method, the sample solution is loaded into the device and the temperature is cycled in time, much like a conventional PCR instrument. In the second method, the sample solution is pumped continuously through spatially varying temperature zones.
For example, Lagally et al. (Anal Chem 73:565-570 (2001)) demonstrated amplification and detection of single template DNA in a 280 nl PCR chamber. Detection of products was made post-PCR using capillary electrophoresis. On the other hand, Kopp et al. (Science 280:1046-1048 (1998)) demonstrated continuous-flow PCR using a glass substrate with a serpentine channel passing over three constant temperature zones at 95° C. (denature), 72° C. (extension), and 60° C. (annealing). The 72° C. zone was located in the central region and had to be passed through briefly in going from 95° C. to 60° C.
Detection was made post-PCR using gel electrophoresis. Since this PCR technique is not based on heating the entire surfaces of the reaction vessel, the reaction rate is determined by a flow rate, not a heating/cooling rate. Neither of these references described real-time monitoring of the PCR reaction.
Park et al. (Anal Chem 75:6029-6033 (2003)) describe a continuous-flow PCR device that uses a polyimide coated fused silica capillary wrapped into a helix around three temperature-controlled blocks. Sample volumes were 2 μl. Detection was made post PCR using gel electrophoresis. Reference was made to the possibility of adapting their instrument for real-time PCR by using a capillary coated with PTFE instead of non-transparent polyimide. See also, Hahn et al. (WO 2005/075683).
Enzelberger et al. (U.S. Pat. No. 6,960,437) describe a microfluidic device that includes a rotary channel having three temperature zones. A number of integrated valves and pumps are used to introduce the sample and to pump it through the zones in a rotary fashion.
Knapp et al. (U.S. Patent Application Publication No. 2005/0042639) describe a microfluidic device capable of single molecule amplification. A planar glass device with several straight parallel channels is disclosed. A mixture of target DNA and PCR reagents is injected into these channels. In a first embodiment, the channels are filled with this mixture and flow is stopped. Then the entire length of the channels is thermally cycled. After thermal cycling is completed, the channels are imaged in order to detect regions of fluorescence where DNA has been amplified. In a second embodiment, the PCR mixture flows continuously through the amplification zone as the temperature is cycled, and fluorescence is detected downstream of the amplification zone. Different degrees of amplification are achieved by altering the time spent in cycling, through changing distance traveled under cycling, and the like. It is worth noting that this method varies conditions (such as cycles experienced) for separate consecutive sample elements, rather than monitoring the progress of individual sample elements over time.
A need exists for robust, high throughput methods of real-time PCR that can be performed efficiently and accurately.


The device for purifying a flow of liquid by means of ultraviolet radiation, includes an elongated ultraviolet lamp; a generally tubular inner casing surrounding substantially the lamp, the casing being made of a material that allows transmission of ultraviolet radiation, the casing having an aperture at each end thereof from which the electrical terminals of the lamp protrude; and a generally tubular outer casing surrounding the inner casing and forming with it a flow passage, the outer casing being provided at substantially each of its ends with inlet and outlet for the flow of liquid. Two connectors are disposed respectively at both ends of the device for securing the lamp and the inner casing with respect to the outer casing. Each connector includes an annular liquid-tight removable seal disposed between inner and outer casings; an opaque electrical socket having a central cavity for receiving the corresponding terminal of the lamp; and a fixing device for securing the corresponding socket and seal with respect to said casings and lamp.

The present invention relates to a device for purifying a flow of liquid by means of ultraviolet radiation.
Known in the art, there is the German Patent No. 3,117,473, showing a device for purifying water by means of ultraviolet radiation. One of the drawbacks with this device is that the ultraviolet lamp is directly exposed to ambient atmosphere so that when the device is operating, ultraviolet rays are emitted at each end of the device. This can be dangerous for children looking directly at the ultraviolet lamp.
Also, when the user wants to replace the lamp, the removing of the lamp cannot be done in a simple operation.
Also known in the art, there is the U.S. Pat. No. 4,752,401, granted on Jun. 21, 1988, and assigned to the company Safe Water Systems International. This patent describes a water treatment system for swimming pools and potable water.
One problem with this system is that when the ultraviolet lamp has to be replaced, this cannot be done in a simple operation. Also, the ultraviolet lamp is directly in contact with the water flow, which is hazardous.
Also known in the art, there are the following patents:
______________________________________ Canadian Patent No.: 1,054,331 Douglas LAMBERT et al 1979 German Patent Nos.: 1,545,595 3,624,169 U.S. Pat. No.: 5,026,477 J-C YEN 1991. ______________________________________
None of the above-mentioned patents can provide a safe device that does not emit ultraviolet rays in the ambient atmosphere and a device that can provide the necessary means for easily replacing the ultraviolet lamp when it is needed.
It is an object of the present invention to provide a device for purifying a flow of liquid by means of ultraviolet radiation that is safe to operate, and that provides means by which the ultraviolet lamp can easily be replaced when it is needed.

Device for purifying a flow of liquid by means of ultraviolet radiation


A system for outputting electronic mail information, which cannot be fully displayed in a portable terminal in another terminal is provided. A mail server receives electronic mail information and determines whether or not the electronic mail information can be outputted in a destination (portable terminal) of the electronic mail information. If it is determined that the electronic mail information cannot be outputted, a P service server issues code information for outputting the electronic mail information in another terminal (P service terminal) and notifies the destination of that effect.

1. Field of the Invention
The present invention relates to an information providing system and device for providing information to users using an electronic mailing system, and a method thereof, a program for the method and a storage medium storing the program.
2. Related Background Art
In recent years, an information providing service utilizing the Internet has become available by the development of a communication infrastructure and an information communication technology. The information providing service utilizing the Internet can provide not only information by means of characters but also multimedia information including images, sounds or the like.
In addition, a user can communicate and exchange information using electronic mails with other users by registering a mail account for using electronic mails.
Although electronic mail information is usually in a text format, a binary file such as application data (a document file) prepared by a user can also be transmitted and received among users as an attachment to the electronic mail information by the technologies for encoding binary data into text data and decoding text data into binary data.
On the other hand, because of the development of a wireless communication infrastructure and an information communication technology therefor as well as the advancement of miniaturization of a terminal for utilizing them, connection to the Internet has become possible not only from a desktop personal computer but also from a portable terminal for a mobile environment such as a cellular phone. As a result, the number of users who send electronic mails using portable terminals is increasing rapidly.
Means for obtaining information circulating over the Internet is no longer limited to a personal computer but are now available in huge variety such as a portable terminal and an electronic mail dedicated terminal. There are a variety of physical limitations and capability limitations peculiar to each of such means, for example a limitation on an amount of information that can be received, a limitation on displaying capability (size, color, resolution or the like) of terminals or the like. In addition, even in communication and exchanges of electronic mails between personal computers that have fewer limitations on displaying capability compared with portable terminals, both a sender and a receiver of information often lack a common information processing environment.
Under such an environment, unless both the users understand each other's environment in advance and exchanges information in the manner matching the other's environment, information that cannot be handled is discarded as it is.
For example, in a portable terminal such as a cellular phone, limitations are set on a number of receivable characters for one mail and information contents (attached files) that can be handled in the case in which electronic mails are exchanged via the Internet. If a receiver utilizes such a portable terminal, information that cannot be handled by the portable terminal (characters exceeding the number of characters allowed for one mail and an attached file that cannot be handled) is discarded in the portable terminal as it is or discarded on a server side.
If a destination user utilizes a mail address provided by a portable telephone carrier, it can be imagined from its domain name that the destination user uses a cellular phone. However, not all users of portable terminals utilize such mail addresses. In general, even a user of a portable terminal utilizes a standard address system of an Internet mail. Moreover, some users of portable terminals transfer mail addresses that are utilized in terminals, such as desktop personal computers, with different limitations on receipts of electronic mails to mail addresses of portable terminals. Thus, the user on a transmitting side cannot easily determine the information receiving capability of a receiver terminal. As a result, it is also extremely hard for a sender of an electronic mail to estimate an environment of a receiver to process the mail into a format compatible with the receiver's environment and send it to the receiver.
Therefore, there are frequent occurrences of mails lacking the information in the exchanges of electronic mails through portable terminals.
If a capacity of information that is receivable from a WWW (World Wide Web) server is larger than a limitation on the number of characters receivable from an electronic mail server, a user sets environment such that an electronic mail to a portable terminal is transferred to an account of the user on the WWW server from the electronic mail server before it is received in a portable terminal and the electronic mail is viewed through the WWW server, whereby the receivable number of characters in the electronic mail can be increased. However, this merely avoids the limitation on the receivable number of characters in a portable terminal, but cannot handle viewing of a binary file and data acquisition, and further unconditionally transfers an electronic mail to a portable terminal. Thus, a user of a portable terminal always has to confirm if a mail has been transferred to the WWW server, which causes significant load to the user of the portable terminal.
In addition, it is not practical, due to limitations on a displaying capability, processing capability or the like of a portable terminal, for a sender of an electronic mail to attach a document file or the like prepared by using an application if only the portable terminal is utilized as connecting means to the Internet.
Moreover, even in receiving means such as a desktop personal computer besides a portable terminal, which is an Internet connection terminal having fewer limitations, requires an application that is used when a sender of the electronic mail prepared an attached document or an application having compatibility with the application in order to develop and display the document to be attached to the electronic mail. However, such applications do not always exist in an electronic mail receiving terminal. In this case, an electronic mail receiver cannot easily see information sent by the electronic mail sender.
Under such an environment, unless a receiver prepares an environment that is compatible with a transmission environment of a sender by consuming a significant amount of labor, information sent from the sender cannot be confirmed.

System for providing electronic mail and device as well as the method, program and storage medium for same


A calcined gypsum treatment apparatus has an agitating type of cooler provided with a cooling region for cooling the calcined gypsum, and a moisture supplying device for incorporating moisture into the calcined gypsum. The moisture supplying device includes a humid gas-feeding port which introduces humid gas including moisture or steam, directly into the cooling region. The calcined gypsum is introduced through a calcined gypsum introduction port into the cooling region, and the moisture is incorporated into the calcined gypsum to modify the calcined gypsum. The humid gas-feeding port is positioned in vicinity to the calcined gypsum introduction port so as to allow the spouted or delivered flow of the humid gas to be brought into contact with the calcined gypsum immediately after introduced into the cooling region.

The calcined gypsum (stucco or calcined plaster) is produced by a calcination process in which raw gypsum, such as natural gypsum or chemical gypsum, is calcined solely, or a mixture of different kinds of raw gypsum is heated (calcined). Calcium sulfate dihydrate (CaSO4.2H2O), which is a principal component of the raw gypsum, is converted to calcium sulfate hemihydrate (CaSO4.½H2O) by the calcination process. The combined water (crystallized water) content of the calcium sulfate dihydrate and the content of the calcium sulfate hemihydrate are 20.9 wt % and 6.2 wt % (theoretical values), respectively. In general, the calcined gypsum obtained by the calcination process further includes III type anhydrous gypsum (CaSO4) and so forth.
The calcined gypsum has a property where the calcined gypsum is slurried by adding an appropriate amount of water thereto and stirring it together with water, thereby being dihydrated and rapidly solidified by a hydration reaction. Therefore, the calcined gypsum is used as a raw material for producing various kinds of gypsum based products. For example, a gypsum board is known as a typical product produced from the calcined gypsum. In general, the gypsum board is a board or panel for building construction work, which is manufactured by pouring gypsum slurry into a space between upper and lower sheets of paper for gypsum board liner and forcibly drying and cutting it wherein the gypsum slurry is produced by mixing and stirring the calcined gypsum with water and adding thereto adhesive auxiliary agent, set accelerator, foam, and so forth.
In such a step of mixing and stirring the calcined gypsum, water and so on, the III type anhydrous gypsum included in the calcined gypsum has a property of increasing the amount of mixing water required for slurrying the calcined gypsum (referred to as "the amount of mixing water for slurrying the calcined gypsum" or "the amount of mixing water" hereinafter). In the manufacturing process of gypsum boards, an increase of the amount of mixing water tends to result in an increase in the loss of heat during a forcibly drying step. Therefore, from a viewpoint of environment load reduction, energy saving measures, and so forth, it is desirable to preliminarily convert the III type anhydrous gypsum to the calcium sulfate hemihydrate before slurrying the calcined gypsum, thereby reducing the amount of mixing water for slurrying the calcined gypsum.
As a technical approach for reducing the amount of mixing water for slurrying the calcined gypsum, it is disclosed in Japanese patent laid-open publication No. 2013-535401 (Patent Literature 1) that, in order to eliminate crystal defects and surface defects of the calcined gypsum, process gas (high temperature and high humidity gas) generated in a furnace or reaction vessel of a calciner is delivered through a fluid passage together with the calcined gypsum, and the calcined gypsum and the process gas are introduced into a gypsum plaster cooler. In this technique, a stabilization zone is provided on an upstream side of a cooling zone of the cooler, and the process gas of the calciner, including a relatively large amount of moisture (steam), is introduced into the stabilization zone together with the calcined gypsum, so that the III type anhydrous gypsum in the calcined gypsum is converted to the calcium sulfate hemihydrate in the stabilization zone by the moisture in the process gas. The calcined gypsum modified or reformed by supply or addition of the moisture is cooled in the cooling zone provided with an air-cooling type of heat exchanger.
As another technical approach for reducing the amount of mixing water for slurrying the calcined gypsum, it is known in the art that the amount of mixing water in the mixing and stirring step is reduced by incorporating water into the calcined gypsum before the mixing and stirring step. For instance, a healing treatment is known in the art, in which a small amount of water (approximately 1 to 10 wt % (weight ratio)) is incorporated into the calcined gypsum before being slurried in order to prevent the particles of the calcined gypsum from causing excessive disintegration and water solubility in a slurrying step (Japanese Patent Publication No. 3-51665 (Patent Literature 2) and Japanese Patent Publication No. 4847855 (Patent Literature 3)).

Calcined gypsum treatment device and calcined gypsum treatment method


In a vehicle air conditioner for heating a passenger compartment by a heater core and a heat pump cycle, when operation of a heat pump cycle is switched from a defrosting operation to a heating assist operation, a heating degree of the heater core is increased higher than a predetermined heating degree. Further, when the operation of the heat pump cycle is switched from the defrosting operation to the heating assist operation, an air outlet mode except for a defrosting mode for defrosting a windshield is set. Further, in the defrosting operation of the heat pump cycle, the temperature of an interior heat exchanger of the heat pump cycle is set higher.

1. Field of the Invention
The present invention relates to a vehicle air conditioner for heating a passenger compartment using both of a heater core and a heat pump cycle. The heat core heats air using exhaust heat generated from the vehicle as a heating source. More particularly, the present invention relates to a control of the vehicle air conditioner, when operation of the heat pump cycle is switched from a defrosting operation to a heating operation.
2. Description of Related Art
In a vehicle air conditioner, air to be blown into a passenger compartment is heated in a heater core using hot water (engine-cooling water) as a heating source. In the vehicle air conditioner, when the temperature of the water flowing into the heater core is low, the temperature of air blown into the passenger compartment is reduced, and a necessary heating capacity cannot be obtained. Accordingly, recently, a heat pump cycle is combined with the heater core for improving the heating capacity. That is, when a necessary heating capacity cannot be obtained only by the heater core, a heating operation is performed by operating an interior heat exchanger of the heat pump cycle as a radiator. When the heating operation is performed in the heat pump cycle, a surface of the exterior heat exchanger is readily frosted. When the heat pump cycle is operated while the surface of the exterior heat exchanger is frosted, heat absorption efficiency of the exterior heat exchanger is reduced. In this case, generally, a defrosting operation of the exterior heat exchanger is performed by operating the exterior heat exchanger as a radiator.
On the other hand, after a predetermined time (e.g., one hour) passes after starting an engine, the temperature of hot water is increased, and the necessary heating capacity can be obtained only by the heater core. Accordingly, the heating operation in the heat pump cycle becomes unnecessary at about a time where the surface of the exterior heat exchanger is frosted, for example. Even in this case, when an outside air temperature is equal to or lower than 0° C., because the frost formed once on the surface of the exterior heat exchanger does not melt, the defrosting operation of the exterior heat exchanger is needed to be performed before the heat pump cycle is operated next.
However, when the defrosting operation of the exterior heat exchanger is performed, condensed water is formed on the surface of the interior heat exchanger due to heat absorption of the interior heat exchanger. Then, when the operation of the heat pump cycle is switched from the defrosting operation to the heating operation in such a case where the temperature of the hot water is again reduced, the condensed water on the interior heat exchanger is evaporated due to heat radiation of the interior heat exchanger. Therefore, a windshield of the vehicle may be fogged.

Vehicle air conditioner with defrosting operation in exterior heat exchanger


Disclosed is a method of manufacturing ultraprecise lenses, including aspherical lenses, not requiring grinding or polishing after press molding. The method comprises heating a glass material to a temperature corresponding to a glass viscosity of from 105 to 109 dPaS so that the glass material is softened, and press molding the glass material with the pressing molds which are heated to a temperature corresponding to a glass viscosity of from 108 to 1012 dPaS. Provided that the glass material is not heated to a temperature as high as that corresponding to a glass viscosity of 105 dPaS when the pressing mold is heated to a temperature corresponding to a glass viscosity of 108 and that the glass material is not heated to a temperature as low as that corresponding to a glass viscosity of 109 dPaS when the pressing mold is heated to a temperature corresponding to a glass viscosity of 1012 dPaS. The glass material to be molded comprises at least one selected from the group consisting of Nb2O3, WO3, and TiO2 and has a refractive index nd of greater than or equal to 1.65, an Abbè number (ν d) of less than or equal to 35, and a sag point (Ts) of less than or equal to 570° C. Each of the pressing molds comprises a film comprising carbon on a molding surface.

In recent years, the need for optical elements employing high-refractive-index, high-dispersion glass has increased immensely. Such glass optical elements are extremely important optical components in the optical systems of cameras and digital cameras, in particular. Further, methods of molding aspherical lenses and the like by precision pressing of high-refractive-index, high-dispersion glass without grinding or polishing are required. For example, Japanese Unexamined Patent Publication (KOKAI) Heisei No. 7-10556 describes temperature ranges for a pressing mold and glass material that are suited to precision pressing.
Examples of known high-refractive-index, high-dispersion glass are described in Japanese Unexamined Patent Publications (KOKAI) Heisei No. 1-308843 and Showa No. 62-3103. However, these glasses contain a large amount of PbO. Thus, they are undesirable from an environmental perspective, and present a further problem in that lead is reduced in the molding chamber during the press molding of optical components, precipitating out into the pressing mold. Due to the relatively high sag point of these glass gobs, the molding temperature must be raised. Thus, there is a problem of deterioration of the mold material during molding and a problem of crystals precipitating in the glass during molding.
Further, Japanese Unexamined Patent (KOKAI) Publication No. 2001-58845 discloses a high-refractive-index, high-dispersion glass with a refractive index (nd) equal to or greater than 1.83 and an Abbé number (νd) of less than or equal to 26. However, when this glass is heated to a temperature suited to press molding, components tending to reduce (Nb2O5, WO3, TiO2) react at the mold surface, causing problems by damaging the release film applied on the mold surface, generating bubbles on the surface of the glass material, and producing radial line marks on the surface of the element following pressing. Accordingly, the satisfactory quality of lens is not necessarily obtained.
Accordingly, the object of the present invention is to provide a method of manufacturing glass optical elements by press molding high-refractive-index, high-dispersion glass without damaging the release film applied on the mold surface, without generating bubbles on the glass material surface, and without generating radial line marks on the optical element surface, while preventing cracking during molding.

Method of manufacturing glass optical elements


A center of gravity Q1 of a mirror structure 31, which has a plurality of mirrors 32, is located between the plurality of mirrors 32. A driving mechanism 40 that rotates the mirror structure 31 includes a first rotational shaft 52 that has a first rotational axis A1 as a central axis and is supported by a supporting base 80 to be rotatable, a first drive device 60 that rotates the first rotational shaft 52, a second rotational shaft 42 that has the mirror structure 31 fixed thereto, has a second rotational axis A2 which is orthogonal to the first rotational axis A1 as a central axis, and is mounted on the first rotational shaft 52 to be rotatable, and a second drive device 45 that rotates the second rotational shaft 42. The center of gravity Q1 of the mirror structure 31 is located in the first rotational shaft 52 and in the second rotational shaft 42.

In recent years, a number of facilities that use heat energy which is obtained by collecting sunlight as environmentally-friendly clean energy at a predetermined position have been developed.
In the related art, PTLs 1 to 4 below disclose solar concentrators that collect the sunlight at predetermined positions.
The solar concentrator described in PTL 1 includes a mirror structure that has a plurality of mirrors, and a driving mechanism that rotates the mirror structure about two rotational axes with different orientations. The driving mechanism has a first rotational shaft that is parallel with the Earth's axis, a second rotational shaft that extends in a direction which is perpendicular to the first rotational shaft, and a drive device that rotates each of the rotational shafts. A flat plate is fixed to an outer circumferential surface of the first rotational shaft. The second rotational shaft is supported by a bearing, which is disposed on the flat plate, to be rotatable. The mirror structure is fixed to the second rotational shaft.
The solar concentrator described in PTL 2 includes a right ascension axis as a polar axis that is parallel with the Earth's axis, a columnar declination axis that is disposed at a tip end of the right ascension axis, a drive device that rotates each of the right ascension axis and the declination axis, a frame that is mounted on an outer circumferential side of the columnar declination axis, and a mirror that is mounted on the frame via a pin.
The solar concentrator described in PTL 3 includes a mirror structure that has a plurality of mirrors, and a driving mechanism that directs the mirrors of the mirror structure in a desired direction. The mirror structure further has, along with the plurality of mirrors, a laminate sheet that adheres to a back surface of the mirror, a truss structure that is arranged on a back surface side of the laminate sheet, and a spacer piece that is arranged between the laminate sheet and the truss structure to maintain a curved surface of the mirror.
A deformable thin mirror is used in the mirror structure to achieve weight reduction, and the mirror is supported, not to be deformed, by the spacer piece and the truss structure which form a rigid body.
The solar concentrator described in PTL 4 also includes a mirror structure that has a mirror. The mirror structure includes the mirror, a plurality of first beams that are curved in conjunction with a desired curved surface of the mirror, and a plurality of second beams that are orthogonal to the plurality of first beams and connect the plurality of first beams with each other.

Solar concentrator, and heat collection apparatus and solar thermal power generation apparatus including same


A rescue device which attaches to the frame of a self-contained breathing apparatus carried on the back of emergency workers such as firemen, hazardous-waste cleanup crews, and other individuals entering into hostile environments. The rescue device is adapted to connect to the frame of existing self-contained breathing apparatus frames or racks. In one form, the rescue device has a top and bottom frame which connects to the SCBA frame at the top and bottom locations. The frames project around the body of the SCBA tank and extend out to position rolling elements for providing the transportation needs. The frames have at the rolling elements ends wheel forks which contain wheels having axles. In another embodiment a skid plate is attached to the ends of the frames in conjunction with the protruding wheels or by itself without rolling elements. Other ways of creating the reduction in frictional drag are provided such as a sled type configuration and a track system.

a) Field of the Invention
Generally speaking, the field of this concept relates to apparatuses for extracting injured emergency care workers or emergency workers such as firemen, first aid, first response, industrial hazard workers, military rescue personnel, and other individuals who enter into highly hostile environments. The concept deals with attaching in some form a transportation device to the back of the injured emergency worker to facilitate ease of transportation or extraction of the injured personnel out of the hostile environment.
b) Background Art
Self-contained breathing apparatuses or SCBAs are used by emergency workers such as firemen, first aid, first response, industrial hazard workers, military rescue personnel, and other individuals who enter into highly hostile environments to mitigate the emergency. These hostile environments include earthquake zones, fire zones, industrial contamination sites such as natural gas leaks, and other areas which require the use of a self-contained breathing apparatus to enable the emergency worker to operate within that hostile environment.
In discussing fire departments and fire response teams, there are specific modes of operation or standards in place to rescue a fireman who has been injured and incapacitated. Generally the firemen entering into a superheated environment weigh between 250-300 lbs. gross weight making it very difficult to extract the fireman from the burning building. Therefore the firemen train for that specific weight and cannot in certain instances qualifies for positions on the fire department team if they cannot pull the dead weight of such an injured fireman. In addition, when an actual fireman is injured in a burning building for example, the rescue team is made up of 3-4 firemen entering into the building to extract the injured team member. They may have to take in equipment to adequately secure the injured team member so as not to further exacerbate the individual's injury, or it may be that the grouping of 3-4 individuals makes it cumbersome to extract the injured person.
The following prior art discusses in some form rescue devices for transporting an injured rescue worker or injured person.
U.S. Pat. No. 6,845,533 (Tulette) discloses a patient transport board which seems to be used for ambulance and emergency care workers. The board has a flat rigid surface on which the patient lies and restraining straps are provided to secure the patient. At the back of the rigid board are a pair of foldable rail members which run the entire length of the board and which are attached to the outside longitudinal edge of the board and can be pivoted and extended so that the patient can be moved down a flight of stairs. A skid plate is also provided at the foot end of the board to allow for positioning of the patient in somewhat of an upright position when moving through tight spaces.
U.S. Pat. No. 6,824,150 (Simione) discloses a cart for transportation of personnel and material in hazardous environments. The cart is made of fire protective materials and is also designed to be buoyant and float. In general, this seems to be more of a gurney-type transportation device which has extendable head frame and leg frame support portions and is also designed to be separately brought into the emergency situation at which time the rescuers would load the injured individual onto the gurney.
U.S. Pat. No. 6,799,769 (Ziolkowski) discloses a welding cylinder dolly or in other words a hand truck, which enables individuals to load, unload and transport cylindrical objects from one location to another. The hand truck or transport uses a pair of vertical support members which act together and form a forwardly facing contact area joined by a cross member having a recessed configuration. An adjustable restraining strap has a free end with an attachment member and an opposing anchor end to substantially encircle the cylindrical object and frictionally retain it between the cross members and the restraining strap.
U.S. Pat. No. 6,565,103 (Wilson) discloses a scuba tank caddie having an optional gear drying rack and an optional portable shower, and its method of fabrication. Referring to column 2 at line 65, the scuba tank caddie has a tank holder which holds at least one tank. The tank holder has a top and a bottom with a rear wall and floor for supporting the tank itself, an axle which is two ends and is rotatably mounted to the tank holder and two wheels. The wheels may be retractable for using the caddie in water and also storage of the caddie when not in use. The retracting means in the current embodiment is an over center cam lever. A handle has a handle stem and handle bar which is coaxially oriented and can be collapsed or extended. Also further down in column 3 at line 57, a reservoir is provided for storing a volume of fresh water in combination with a low pressure quick disconnect hose to transmit the fluid from the reservoir to a showerhead to provide for showering.
U.S. Pat. No. 6,341,789 (Checa et al) discloses a two wheeled hand cart for transporting scuba gear. As you and I previously discussed, transportation of the scuba gear is very similar to the self-contained breathing apparatus which firemen and rescue workers use. Thus the scuba transportation devices are somewhat relevant, although one element is generally missing from these concepts and that is the addition of the person being rescued onto the back of the scuba tank. The cart in this situation comprises an elongated sheet having a top end and a bottom end, a planar front surface and a generally planar back surface. At the base is attached a pair of guides or wheels which are connected between an elongated shaft. The scuba gear can be loaded onto this hand cart and transported to the dive location.
U.S. Pat. No. 6,047,983 (Day) discloses a portable combination hand truck and valet valise. The hand truck has a hinged double shell which is foldable into a closed position, creating a tube like enclosure when stored, and when opened provides the frame for the hand cart. Referring to column 2 around line 12, a pair of wheels are sized to fit within the tube and adapted for easy attachment to and detachment from the axle. A handle is attachable to the hinged double shell in the open position.
U.S. Pat. No. 5,947,351 (Garofalo et al) discloses a cylinder carrier which is made of an elongated post and includes a sleeve and an extension piece retained within the sleeve. The extension piece has a handle at the protruding end to operate the carrier. At the base of the carrier are a pair of cylinder rests on either side of the vertical sleeve. The cylinder rests can be folded up against the vertical sleeve for storage. Cylinder straps are positioned approximately mid-height of the vertical sleeve and are disposed to retain the cylinders on top of the rests. A pair of shoulder straps are attached to the vertical sleeve or post to be worn on the back of the carrier. Two small wheels are located at the bottom or base of the vertical post or sleeve for transportation.
U.S. Pat. No. 5,492,346 (Stadler et al) discloses a scuba tote which has wheels at the base and a cover with formfitting recesses to store the scuba tanks. Within the recesses at the top and bottom, are shelves to maintain the position of the tanks. The interior of the cover or body is sealed to keep a constant atmospheric pressure for pressure equalization purposes.
U.S. Pat. No. 5,393,080 (Ross) discloses an aquatic air tank dolly which has a cup to secure the base of the tank and supports connected to wheels for conveniently moving the tank. Side rails are attached to the cup at the base of the tank and also attached to the valve stem at the top of the tank. The side rails are adapted for supporting additional diving equipment
U.S. Pat. No. 5,131,670 (Clements et al) discloses a detachable scuba tank overland transport device which enables users to move scuba tanks over ground instead of having to carry the device. The transport has an elongated axle with a wheel rotatably mounted at the ends of the axle. Two small tank-engaging members are provided and connected to the axle. The tank-engaging members are rotatable about the axle from a stored position to an open position. One of the members has a support platform for supporting the scuba tank; each member has a sidewall engaging portion for engaging the sidewall of a scuba tank inserted between the sidewall engaging portions and resting upon the support platform.
U.S. Pat. No. 4,848,714 (Ziaylek Jr. et al) discloses a mounting plate with rollers, the mounting plate is the type that is generally used by firemen or firefighters and rescue or emergency squads. The rollers themselves are connected to the free ends of the springlike clamp arms which contain the air cylinder. The location and extent or projection of the rollers on the clamp arms makes the insertion and removal of the air cylinders or self-contained breathing apparatus more efficient.
U.S. Pat. No. 4,815,761 (Henderson) discloses an amphibious scuba assist device which is designed to help diverse transport scuba tanks and other diving gear across sandy beaches and other shoreline and also is provided as an offshore floating work platform and a dive flag holder during diving operations. The frame is configured using a hollow tubing and has a forward member, a rearward or aft member, and two side members. Handle members extend along the sides and support the buoyant plastic foam cylinders connected to the handle. The frame carriers support surface and straps retain the tanks and other gear on the frame.


A digital work (102) and copyright management information (103) for the digital work are recorded on an information recording medium (101) by altering a shape, a position or a pattern (104, 105) of recording mark edges of the digital work. Alternatively, a decryption key for the right management information is recorded on an information recording medium on which the copyright management information has been recorded encrypted, by altering the recording mark edges of the copyright management information. Alternatively, a check code for the copyright management information is recorded on the information recording medium by altering the recording mark edges. The check code is checked when the copyright management information is read, thus detecting illegal use of the copyright management information.

Optical discs, of which DVDs (Digital Versatile/Video Discs) are representative, have become common as recording media for recording large amounts of digital data, such as AV (audio/video) data and computer data. For example, playback-only optical discs having two hours or more of high-quality moving images recorded thereon are on the market. Such digital data that is subject to copyright is called a digital copyrighted work (hereinafter referred to simply a "digital work").
In recent years, content scrambling systems have been introduced to prevent digital works being copied illegally to other recording media. For descriptions of such systems, refer to Makoto TATEBAYASHI et al., "DVD Content Scramble System", ITE Technical Report Vol. 21, No. 31, pp. 15-19, VIR '97-26 (May, 1997), and NIKKEI ELECTRONICS, Nov. 18, 1996 (No. 676), pp. 13-14.
A content scrambling system scrambles compressed digital content, such as a movie, with use of three layers of secret keys (a title key, a disc key and a master key), and records the scrambled data on an information recording medium in a user information area that is accessible by a user.
The most important of the secret keys, the master key, is known only to manufacturers who have a legitimate license. The disc key and the title key, which are unique to each DVD and each title respectively, are scrambled based on the master key and stored on the information recording medium in a control information area that is not accessible by the user. This restricts access by the user to the secret keys that are necessary for unscrambling, and therefore prevents the digital content being copied illegally by means such as copying files.
The focus of research and development in the field of scrambling in recent years has been moving away from copyright protection for protecting copyrighted information and towards copyright control that provides digital copyrighted works conveniently for the user.
SD memory cards, which are semiconductor memories, are exemplary of such convenience for the user. Such an information recording medium (hereinafter referred to simply as a "recording medium") is provided with a protected area in addition to the user area. The protected area, which is accessible only by the system, stores copyright management information relating to rights for moving, copying, or the like, of the corresponding digital work. This enables the digital work to be moved or copied within the scope of the rights.
FIG. 1 illustrates a method proposed in Japanese patent no. 2981448 for one type of copyright management, specifically, moving a digital work between recording media when the recording media do not have protected areas for recording copyright management information.
This method realizes safe movement of a digital work by first moving the digital work that is recorded in a recording area 2003 of a first medium 2001 to a recording area 2005 of a second medium 2002, and then deleting management information 2004 of the first medium 2001 that includes position information of the recording area 2003.
However, in this method, the digital work can be moved freely, and it is not possible to control, for example, the number of times that the digital work is permitted to be moved. Furthermore, even if the move times is managed by recording such information in the user area, the user may tamper with the information. If usage rights of a digital work recorded on an optical disc are to be controlled, it is necessary to provide a protected area such as described for semiconductor memories on the optical disc.
To provide a protected area that is not accessed by the user, it is impossible to use a physical medium efficiently. Furthermore, in order to implement rights management in a recording medium, such as an optical disc, that does not have a protected area for recording copyright management information, it would be necessary to change the specifications of the recording medium itself. For these reasons, rights management is not presently implemented in such recording media.
The object of the present invention, which solves this problem, is to provide a recording medium that prevents a digital copyrighted work that is recorded thereon from being copied exactly as is, and, even in a recording medium that does not have a separate protected area, enables rights management of recorded digital copyrighted works; and an usage method for the recording medium.

Information recording medium, usage management method, and usage management apparatus


A method of optimizing a fast dynamic channel allocation call admission control algorithm in a wireless communication system includes a pre-code allocation process, a signal-independent code allocation process, and a post-code allocation process. The pre-code allocation process includes receiving and processing a request message and obtaining system measurements and information from a centralized database. The code allocation process begins by checking the availability of a code set in the cell and generating timeslot sequences for the available timeslots. A code set is assigned to the available timeslots in a timeslot sequence, wherein a successful assignment is a solution. The interference signal code power (ISCP) is calculated for each solution and the solution having the lowest weighted ISCP is selected as an optimal solution. The post-code allocation process includes storing allocation information in a centralized database and creating a response message.

In wireless communication systems, RRM is generally responsible for utilizing the air interface resources. RRM is used to guarantee quality of service (QoS), to provide efficient use of the radio resources, and to increase system capacity. RRM consists of admission control, handover, power control, and congestion control functionalities. Admission control can be divided into user admission control and call admission control. User admission control accepts or rejects the radio resource control (RRC) connection requested by a wireless transmit/receive unit (WTRU). Call admission control accepts or rejects a request to establish or modify a radio access bearer (RAB) in the radio access network (RAN). Call admission control is located in the controlling radio network controller (C-RNC).
There are two dynamic channel allocation (DCA) functions, slow DCA and fast DCA (S-DCA, F-DCA). The S-DCA allocates the radio resources to cells while the F-DCA allocates the radio resources to bearer service. The F-DCA call admission control functions are responsible for efficiently allocating or changing the allocations of physical resources. When a request for physical resources is received, the call admission control will accept or reject the request based on the availability of physical resources and interference level in the cell. The request can be accepted only if both uplink and downlink call admission control admit it. Otherwise, the request is rejected.
In order to guarantee the QoS and minimize the interference, a certain F-DCA call admission control algorithm has been currently implemented. But the previous implementation of the F-DCA call admission control algorithm has several limitations. One limitation is that it is difficult to be reused by other RRM functions since the main interface function is large and the inputs to the code allocation function (which forms the core function of the F-DCA call admission control algorithm) are dependent on the signal message. A second limitation is that the past implementation of the F-DCA CAC algorithm is generally only suitable for real time (RT) service.
It is desirable to provide an optimized implementation of the F-DCA CAC algorithm which is suitable for RT and NRT (non-real time), and which overcomes the disadvantages of the known algorithms.

This patent is subject to a terminal disclaimer.

Method of optimizing an implementation of fast-dynamic channel allocation call admission control in radio resource management


A fluorogenic lifting strip containing titanium dioxide has been successful in the lifting and enhancement of impressions and bloody impressions from nonporous, semi porous and porous surfaces. The lifting strip is best when activated with an alcohol such as ethanol or methanol. When the lifting strip has dried after application it can easily be removed from the surface lifting the impression onto a contrasting white background. The lifting trip can be subsequently visualized with an ALS or Laser to fluoresce the lifted impression with optimal contrast for visualization and examination. This method is safe, easy, and effective on several surfaces of contrasting colors.

Various impressions are frequently encountered at crime scenes and are of great importance to law enforcement officials. Impressions can include fingerprints, bloody fingerprints, hand prints, palm prints, foot prints, footwear prints, etc. Other than blood, proteinaceous impressions can include sebaceous, eccrine, saliva, semen, and vaginal secretions. Therefore, developing impressions and bloody proteinaceous impressions on various surfaces is of great interest to the forensic science community. Every finger and palm print, for example, has a series of elevated patterns known as friction ridges which are unique to each individual in the population. As a result, if friction ridges can be visualized in blood, they can be used for identification purposes.
When bloody impressions are located on light-colored surfaces they may be photographed directly, which may provide some visualization of the ridge structure. But when bloody impressions are located on dark colored surfaces there is usually not enough contrast between the bloody impression and the surface to visualize any ridge structure in the impression. Currently, there are a variety of techniques for enhancing bloody impressions on some non-porous, semi-porous and porous surfaces of varying contrasts, yet they are limited in their effectiveness (Caldwell and Kim 2002; Forsythe-Erman 2001; McCarthy and Grieve 1988; Sears and Prizeman 2000; Sears and others 2001; Sears and others 2005; Yapping and Yue 2004). These processes require using chemical reagents and are normally conducted in a laboratory setting, which may be both inconvenient and time consuming. Furthermore, immovable or bulky objects from crime scenes cannot be brought back to the laboratory for analysis. Many potentially identifiable impressions may only be photographed and not enhanced due to limitations of this nature; and this is not in the best interest of society.
Accordingly, the inventor has seen a need for technology that permits law enforcement officials to lift a bloody impression from a crime-scene surface, and to preserve it for further analysis and use. The inventor has also discovered that certain embodiments of the invention are also useful for lifting, preserving, and analyzing prints such as latent fingerprints because these embodiments produce an impression that has fluorescent characteristics when analyzed under certain light sources.

Lifting and preserving bloody impressions for law enforcement


A method, system, and computer program product for evaluating compliance of a user interface design are provided in the illustrative embodiments. A hierarchy of elements of a user interface is received from a first application executing in a client data processing system. A second application presents the user interface including a set of user interface elements at the client data processing system. A compliance rule is selected from a set of compliance rules. An evaluation is made whether an attribute associated with a user interface element meets a condition specified in the compliance rule. Responsive to the evaluating being negative, the user interface element is reported as being non-compliant with the compliance rule.

Almost all data processing systems, including mobile devices, include some manner of interacting with a user. For example, a display device is used with a data processing system for presenting a visual user interface to a user, an audio device is used with the data processing system for presenting audible user interface to the user, and tactile devices are used for presenting a tactile interface to the user. Within the scope of the disclosure, the term "user interface" refers to a user interface of any of these types or other types as may be suitable for a particular implementation.
Accessibility features are features of a user interface that are designed or configured to assist a user in interacting with a particular aspect of a given user interface. For example, a large default font size is an example accessibility feature that makes interacting with a user interface easier for those users who have weak eyesight. Similarly, an audio readout accessibility feature assists users with vision impairment to interact with a user interface. A tactile feedback, such as vibration of a mobile device, is another example accessibility feature for users who have temporary, circumstantial, or permanent auditory impairment.
Many accessibility features are presently available for use in user interface designs. Often, an application executing on a data processing system presents several user interfaces to the user during the course of using the application. For example, numerous user interfaces in the forms of screen layouts, plugin applications, and tools are presented or called upon during the course of a user using a software application.

Evaluating accessibility compliance of a user interface design

INTERNATIONAL BUSINESS MACHINES CORPORATION


A fast Fourier transform circuit includes a computation component, an extraction component and a setting component. The extraction component, at each step of the computation, extracts, from computation result data points calculated by the computation component, data in a pre-specified range with a number of bits the same as a predetermined number of bits, which is an effective range for a butterfly computations. The setting component sets the data points of the predetermined number of bits which have been extracted by the extraction component to serve as input data when butterfly computations of a next step are to be performed by the computation component.

1. Field of the Invention
The present invention relates to a fast Fourier transform circuit and a fast Fourier transform method, and particularly relates to a fast Fourier transform circuit and fast Fourier transform method for applying a discrete-time Fourier transform computation to 2n points of input data, each of a predetermined number of bits (n being a natural number greater than 0), by dividing into a plurality of stages and performing butterfly computations.
2. Description of the Related Art
With the advance of digital technology in recent years, broadcasts such as terrestrial television broadcasts and the like are shifting from analog broadcasting to digital broadcasting. For such digital broadcasts, an orthogonal frequency division multiplexing system below referred to as OFDM) is employed as a modulation system. For demodulation of a carrier wave in OFDM, fast Fourier transforms (below referred to as FFT) are utilized.
These fast Fourier transforms are a technology for reducing the computation volume of a discrete-time Fourier transform below referred to as a DFT). A great many computation technologies have been proposed for these fast Fourier transforms. One generally well-known computation technology is a Cooley-Tukey-based computation technology which performs a discrete-time Fourier transform by performing butterfly computations on input data, divided into a plurality of stages (steps). As a related technology, Japanese patent Application Laid-Open (JP-A) No. 5-266059 has disclosed a technique which improves a processing efficiency of these butterfly computations.
Herebelow, a frequency-thirning Cooley-Tukey-type fast Fourier transform with a radix of 2 will be described. Below, a number of data points N of a discrete-time Fourier transform (a number of data samples) is 4.
A definition equation of a discrete-time Fourier transform is shown by the following equation (1). WN in equation (1) is a twiddle factor.
                              X                                (            k            )                          =                              ∑                          n              =              0                                      N              -              1                                                                                x                                            (                n                )                                      ·                          W              N              nk                                                          (        1        )
Here, WN=e−j2π/N
Hence, a discrete-time Fourier transform with the number of data points being 4 is expressed by the following parallel matrix equation of equation (2).
                              [                                                                      X                                                        (                    0                    )                                                                                X                                                        (                    1                    )                                                                                X                                                        (                    2                    )                                                                                X                                                        (                    3                    )                                                                                ]                =                              [                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      1                                                                                W                      4                      2                                                                                W                      4                      3                                                                                W                      4                      0                                                                                W                      4                      2                                                                                W                      4                      4                                                                                W                      4                      6                                                                                W                      4                      0                                                                                W                      4                      3                                                                                W                      4                      6                                                                                W                      4                      9                                                                                ]                    ·                      [                                                                                x                                                              (                      0                      )                                                                                x                                                              (                      1                      )                                                                                x                                                              (                      2                      )                                                                                x                                                              (                      3                      )                                                                                ]                                              (        2        )
In a Cooley-Tukey-type computation technique, each X(k) (k=1, 2, 3, 4) in the above equation (2) is substituted as in the following equation (3).
                              [                                                                      X                                                        (                    0                    )                                                                                X                                                        (                    2                    )                                                                                X                                                        (                    1                    )                                                                                X                                                        (                    3                    )                                                                                ]                =                              [                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      0                                                                                W                      4                      2                                                                                W                      4                      4                                                                                W                      4                      6                                                                                W                      4                      0                                                                                W                      4                      1                                                                                W                      4                      2                                                                                W                      4                      3                                                                                W                      4                      0                                                                                W                      4                      3                                                                                W                      4                      6                                                                                W                      4                      9                                                                                ]                    ·                      [                                                                                x                                                              (                      0                      )                                                                                x                                                              (                      1                      )                                                                                x                                                              (                      2                      )                                                                                x                                                              (                      3                      )                                                                                ]                                              (        3        )
The 4×4 matrix in equation (3) can be expressed as shown in the following equation (4).
                                          W            ^                    4                =                  [                                                                                W                    4                    0                                                                          W                    4                    0                                                                          W                    4                    0                                                                          W                    4                    0                                                                                W                    4                    0                                                                          W                    4                    2                                                                          W                    4                    4                                                                          W                    4                    6                                                                                W                    4                    0                                                                          W                    4                    1                                                                          W                    4                    2                                                                          W                    4                    3                                                                                W                    4                    0                                                                          W                    4                    3                                                                          W                    4                    6                                                                          W                    4                    9                                                                                ]                                    (        4        )
Now, as is shown in FIG. 9, the twiddle factor WN can be expressed as points on a unit circle in a complex plane. Therefore, the relationships shown in the following equations (5) and (6) apply to the twiddle factor.WN2k=WN/2k  (5)WNnk=WN((nk))N  (6)
Therefore, equation (3) can be rewritten as equation (7).
                                                                                [                                                                                X                                                                                (                            0                            )                                                                                X                                                                                (                            2                            )                                                                                X                                                                                (                            1                            )                                                                                X                                                                                (                            3                            )                                                                                ]                                =                                                                                [                                                                                W                              4                              0                                                                                W                              4                              0                                                                                W                              4                              0                                                                                W                              4                              0                                                                                W                              4                              0                                                                                W                              4                              2                                                                                W                              4                              0                                                                                W                              4                              2                                                                                W                              4                              0                                                                                W                              4                              1                                                                                W                              4                              2                                                                                W                              4                              3                                                                                W                              4                              0                                                                                W                              4                              3                                                                                W                              4                              2                                                                                W                              4                              1                                                                                ]                                    ·                                      [                                                                                x                                                                                (                              0                              )                                                                                x                                                                                (                              1                              )                                                                                x                                                                                (                              2                              )                                                                                x                                                                                (                              3                              )                                                                                ]                                                                                =                                                                                [                                                                                W                              ^                                                        2                                                                                W                              ^                                                        2                                                                                W                                ^                                                            2                                                                                Λ                              2                                                                                -                                                                                W                                  ^                                                                2                                                                                Λ                              2                                                                                ]                                    ·                                      [                                                                                x                                                                                (                              0                              )                                                                                x                                                                                (                              1                              )                                                                                x                                                                                (                              2                              )                                                                                x                                                                                (                              3                              )                                                                                ]                                                                                W              ^                        2                    =                      [                                                                                W                      2                      0                                                                                W                      2                      0                                                                                W                      2                      0                                                                                W                      2                      1                                                                                ]                                                                                Λ            2                    =                      [                                                                                W                    4                    0                                                                    0                                                                              0                                                                      W                    4                    1                                                                        ]                                              (        7        )
Hence, if equation (3) is expressed using a 2×2 zero matrix O2 and a 2×2 unit matrix I2, the following equation (8) is produced.
                                                                                [                                                                                X                                                                                (                            0                            )                                                                                X                                                                                (                            2                            )                                                                                X                                                                                (                            1                            )                                                                                X                                                                                (                            3                            )                                                                                ]                                =                                                                                [                                                                                W                              ^                                                        2                                                                                o                            2                                                                                o                            2                                                                                W                              ^                                                        2                                                                                ]                                    ·                                      [                                                                                I                            2                                                                                o                            2                                                                                o                            2                                                                                I                            2                                                                                ]                                    ·                                      [                                                                                I                            2                                                                                I                            2                                                                                I                            2                                                                                -                                                          I                              2                                                                                ]                                    ·                                      [                                                                                x                                                                                (                              0                              )                                                                                x                                                                                (                              1                              )                                                                                x                                                                                (                              2                              )                                                                                x                                                                                (                              3                              )                                                                                ]                                                                                =                                                                                [                                                                                1                                                                          1                                                                          0                                                                          0                                                                                1                                                                                -                            1                                                                                0                                                                          0                                                                                0                                                                          0                                                                          1                                                                          1                                                                                0                                                                          0                                                                          1                                                                                -                            1                                                                                ]                                    ·                                      [                                                                                1                                                                          0                                                                          0                                                                          0                                                                                0                                                                          1                                                                          0                                                                          0                                                                                0                                                                          0                                                                                W                            4                            0                                                                                0                                                                                0                                                                          0                                                                          0                                                                                W                            4                            0                                                                                ]                                    ·                                                                                [                                                                                1                                                                          0                                                                          1                                                                          0                                                                                0                                                                          1                                                                          0                                                                          1                                                                                1                                                                          0                                                                          1                                                                          0                                                                                0                                                                          1                                                                          0                                                                                -                            1                                                                                ]                                    ·                                      [                                                                                x                                                                                (                              0                              )                                                                                x                                                                                (                              1                              )                                                                                x                                                                                (                              2                              )                                                                                x                                                                                (                              3                              )                                                                                ]                                                                                (          8          )
That is, a discrete-time Fourier transform with the number of data points N being 4 can be decomposed to be a product or matrices constituted of discrete-time Fourier transforms with numbers of data points N being 2. Such decomposition is not limited to cases in which the number of data points N is 4 but generally applies to cases in which the number of data points N is 2n (where n is a natural number greater than 0).
The decomposition shown in the above equation (8) can be represented as shown in FIG. 10, being represented by a combination of the butterfly computation shown in FIG. 11.
Similarly, taking a discrete-time Fourier transform with the number of data points N being 8 as an example, the discrete-time Fourier transform with the number of data points N of 8 can be decomposed into discrete-time Fourier transforms with numbers of data points N of 4 by sorting the X(k), and the discrete-time Fourier transforms with numbers of data points N of 4 can be further decomposed into discrete-time Fourier transforms with numbers of data points N of 2. This decomposition can be represented as in FIG. 12.
As shown in FIG. 10 (a data point count N=4 fast Fourier transform) and FIG. 12 (a data point count N=8 fast Fourier transform), a fast Fourier transform can be implemented by a combination of butterfly computations, and a number of stages of these butterfly computations can be expressed as log2 N. For example, in the case of a data point count N=8 fast Fourier transform, the number of stages is log2 8=3.
FIG. 13 shows an example of a fixed-point fast Fourier transform circuit 10′ which implements a Cooley-Tukey-type fast Fourier transform.
Operations of this fast Fourier transform circuit 10′, with the radix being 2, will be briefly described for a case of performing a fast Fourier transform with the number of data points N being 8.
(1) Input data to be inputted to the fast Fourier transform circuit 10′ is memorized at an FFT input data storage RAM 12′. A stage control circuit 14′ outputs a stage signal (a signal indicating which stage is in operation) and controls operations of a selector 16′ and an FFT computation section 22′. Initially, the stage control circuit 14′ outputs a stage signal indicating a first stage.
(2) When the stage signal outputted by the stage control circuit 14′ indicates the first stage, data from the FFT input data storage RAM 12′ is selected by the selector 16′, and the data from the FFT input data storage RAM 12′ is inputted to the FFT computation section 22′.
(3) The FFT computation section 22′ reads respective twiddle factors corresponding to the stage indicated by the stage signal from a twiddle factor table 18′, which is memorized at a twiddle factor memorization section 20′, and performs butterfly computations on the data that have been inputted using the respective twiddle factors that have been read.
(4) Results of the butterfly computations are memorized in an FFT computation result storage RAM 28′. When the butterfly computation results have all been memorized to the FFT computation result storage RAM 28′, the stage control circuit 14′ outputs a stage signal indicating the next stage.
(5) When the stage signal outputted by the stage control circuit 14′ indicates the second or a subsequent stage, data from the FFT computation result storage RAM 28′ is selected by the selector 16′, and the data from the FFT computation result storage RAM 28′ is inputted to the FFT computation section 22′.
(6) Thereafter, the operations of (3) to (5) above are repeated, for a number of stages corresponding to the data point count N.
(7) After the butterfly computations for the number of stages have been completed (i.e., if the data point count N is 8, after three stages have been completed), the data that has been memorized to the FFT computation result storage RAM 28′ serves as output data of the fast Fourier transform.
Now, in a case in which the above-described Cooley-Tukey-type fast Fourier transform computation is practically implemented in hardware, data of unlimited bit widths cannot be held in the FFT input data storage RAM 12′, the FFT computation result storage RAM 28′, the FFT computation section 22′ and the like (FIG. 13). Therefore, a bit width limitation is inherent in the circuit.
For example, bit widths for one data point in the FFT input data storage RAM 12′ and the FFT computation result storage RAM 28′ may be limited to 16 bits, and a bit width of each twiddle factor WNi may be 10 bits. In such a case, as shown in FIG. 14, one cycle of addition of 16 bits and one multiplication of an addition result with the twiddle factor are performed. Therefore, data widths of output data points which are outputted as results of the butterfly computations by the FFT computation section 22′ are up to 27 bits.
However, the bit width of the FFT computation result storage RAM 28′ is limited to 16 bits. Therefore, in this conventional fast Fourier transform circuit 10′, as shown in FIG. 15, it is necessary to provide a bit extraction section 24′, to extract 16 bits of data from the 27 bits with the bit extraction section 24′, and store the 16 bits of data in the FFT computation result storage RAM 28′.
At this bit extraction section 24′, which 16 bits of data to extract from the 27 bits is specified beforehand. For example, extraction may always be fixedly applied, to always extract the most significant 16 bits of data of a 27-bit signal, or the like.
However, if the range of data to be extracted by the bit extraction section 24′ is fixed thus, the data extraction range may not be an appropriate range, depending on characteristics of input data that are inputted to the fast Fourier transform circuit 10′ (the size of an amplitude value, whether randomness is high or low, whether the data is an impulse with a localized peak, and so forth). Hence, if the data extraction range is not a suitable range, overflows/underflows, errors and the like may occur during computation of a fast Fourier transform, and a final computation error of the fast Fourier transform may be large, which is a problem.

Fast fourier transform circuit and fast fourier transform method