Phototherapeutic instruments are disclosed having integral stopper devices which limit the penetration of an optical fiber during tissue penetrating phototherapy. In one preferred embodiment, a fluted outer sheath is disposed about an internal optical fiber. The fluted sheath is configured to expand during penetration of the optical fiber into a patient's tissue. As the fluted elements expand, the present a much larger cross-sectional area which resists further penetration of the instrument beyond a predetermined desirable distance. The invention is useful in limiting an optically-transmissive fiber's penetration and, thereby, reduce the possibility of perforation of a body lumen or organ. The invention is particularly useful in placing a ablative laser radiation device into the ventricle of the heart when performing arrhythmia-correcting laser ablative procedures or when revascularizing the heart percutaneously. The stopper devices limit penetration and stabilize the optically-transmissive tip during such procedures.

The technical field of this invention is phototherapy and, in particular, instruments employing optical fibers or other flexible light waveguides to deliver radiation to a targeted biological sight.
Fiber optic phototherapy is a increasing popular modality for the diagnosis and/or treatment of a wide variety of diseases. For example, in surgery, infrared laser radiation will often be delivered to a surgical site via a hand-held instrument incorporating an optically transmissive fiber in order to coagulate blood vessels or cauterize tissue. Similar fiber optic delivery systems have been proposed for endoscopic or catheter-based instruments to deliver therapeutic radiation to a body lumen or cavity. U.S. Pat. No. 4,336,809 (Clark) and U.S. Reissue Pat. No. RE 34,544 (Spears) disclose that hematoporphyrin dyes and the like selectively accumulate in tumorous tissue and such accumulations can be detected by a characteristic fluorescence under irradiation with blue light. These patents further teach that cancerous tissue that has taken up the dye can be preferentially destroyed by radiation (typically high intensity red light) that is absorbed by the dye molecules during phototherapy.
Others have proposed the use of fiber-delivered radiation to treat artherosclerotic disease. For example, U.S. Pat. No. 4,878,492 (Sinofsky et al.) discloses the used of infrared radiation to heat blood vessel walls during balloon angioplasty in order to fuse the endothelial lining of the blood vessel and seal the surface. Another application of fiber-delivered radiation is disclosed in U.S. Pat. No. 5,053,033 (Clarke) which teaches that restenosis following angioplasty can be inhibited by application of UV radiation to the angioplasty site to kill smooth muscle cells which would otherwise proliferate in response to angioplasty-induced injuries to blood vessel walls.
In yet another application, phototherapeutic instruments are employed to treat electrical arrhythmia of the heart. In such applications, a catheter having a fiber optic component is fed via a major artery into a patient's heart. Once inside the heart, a catheter senses electrical impulses with electrical contacts on its outer sheath or other catheter elements in order to locate the source of arrhythmia. Once located, the phototherapeutic component is activated to "ablate" a portion of the inner heart wall. By coagulating the tissue in the vicinity of the arrhythmia source, the likelihood that the parent's heart will continue to experience arrhythmia is thus reduced.
In other applications, laser radiation can be used in conjunction with a similar catheter instrument inside a patient's heart to increase blood flow to oxygen starved regions of the heart muscle. In such procedures, the laser radiation is used to form small holes into the heart muscle so that the oxygen-depleted tissue is bathed with blood from the ventricular cavity.
In all of these applications, there is the potential for damage to the patient's internal organs, especially the heart, if the light-emitting fiber is inserted too far into the patient's tissue. Particularly, in the case of the heart muscle, perforation of the heart wall can have very dangerous effects.
Accordingly, there exists a need for better apparatus for fiber-optic phototherapy. In particular, devices that can "stop" an optical fiber from perforating a patient's organs would meet a particularly important need in the field of minimally-invasive phototherapeutic surgery. Moreover, a device that can help stabilize the phototherapeutic instrument in operation (such as within the chambers of a rapidly beating heart) would also be particularly useful.

Phototherapy apparatus with integral stopper device


Nucleic acid transporter systems for delivery of nucleic acid to a cell. The nucleic acid transporter includes a binding complex. The binding complex contains a binding molecule which non-covalently binds to the nucleic acid and covalently links to a surface ligand, nuclear ligand and/or a lysis agent. These may be linked to the binding molecule by spacers.

This invention relates to gene therapy using transporter systems for delivering nucleic acid into a cell.
Recombinant retroviral vectors have been used for delivery of genes to cells of living animals. Retroviral vectors permanently integrate the transfered gene into the host chromosal DNA. Studies have demonstrated that retroviral vectors can be transduced into liver cells in vivo by direct injection of the virus into the parenchyma after carbon tetrachloride treatment. Kaleko et al., Human Gene Therapy, Vol. 2, pp. 27-32 (1991). Analysis of transduced liver cells indicated a transduction frequency of about 1 out of 160 liver cells. Id.
Retroviral vectors can be transduced into rat hepatocytes after partial hepatectomy followed by a surgical procedure involving isolation and perfusion of the liver with a viral vector. Poorman et al., Arterioscl. Throm., Vol. 11, p. 1413A (1991); Hobbs et al., Annu. Rev. Genet., Vol. 24, pp. 133-70 (1990). The transduced hepatocytes from the above studies were detectable six months after gene transduction. Id.
Another virus used for gene delivery is adenovirus. It has been developed as a means for gene transfer into epithelial derived tissues. Stratford-Perricaudet et al., Hum. Gene. Ther., Vol. 1, pp. 241-256 (1990); Gilardi et al., FEBS, Vol. 267, pp. 60-62 (1990); Rosenfeld et al., Science, Vol. 252, pp. 4341-4346 (1991). Vectors have been constructed in which the 35 Kb genome in the E3 and E1 regions have been deleted, such that recombinant gene constructs can be inserted into the adenovirus vector. Id. Since adenovirus has a natural tropism for the lung epithelium it was used for gene transfer into this tissue. Gilardi et al., FEBS, Vol. 267, pp. 62-62 (1990); Rosenfeld et al., Cell, Vol. 68, pp. 143-155 (1992).
Recombinant adenoviral vectors have the advantage over retroviruses of being able to transduce non-poliferating cells as well as an ability to produce purified high titer virus. Studies using an adenoviral vector to deliver genes to liver demonstrated that mouse hepatocytes can be transduced in vivo with the vector. Stratford-Perricaudet, Hum. Gene Ther., Vol. 1, pp. 241-256 (1990). Use of adenoviral-mediated transfer of orninthine transcarbamylase cDNA allowed the transfer of enzyme activity to the mouse liver. These studies resulted in phenotypic correction of enzyme deficiency. Id. Other studies have demonstrated human .alpha.-1-antitrypsin production from rat liver after transduction with a recombinant adenoviral vector. Jaffe et al., Nature-Genetics, Vol. 1, pp. 372-378 (1992). These studies determined that 1% of hepatocytes were transduced in vivo. Id.
In addition to retroviral-mediated gene delivery, a more recent means for DNA delivery has been receptor-mediated endocytosis. Endocytosis is the process by which eucaryotic cells continually ingest segments of the plasma membrane in the form of small endocytotic vesicles. Alberts et al., Mol. Biol. of Cell, Garland Publishing Co., New York, 1983. Extracellular fluid and everything dissolved in it becomes trapped in the vesicle and is ingested into the cell. Id. This process of bulk fluid-phase endocytosis can be visualized and quantified using a tracer such as enzyme peroxidase introduced into the extra-cellular fluid. Id. The rate of constitutive endocytosis varies from cell type to cell type.
Endocytotic vesicles form in a variety of sizes and shapes and are usually enlarged by fusing with each other and/or with other intra-cellular vesicles. Stryer, Bioch., Freeman and Co., New York (1988). In most cells the great majority of endocytotic vesicles ultimately fuse with small vesicles called primary lysosomes to form secondary lysosomes which are specialized sites of intra-cellular digestion. Id. The lysosomes contain a wide variety of degradative enzymes to digest the macromolecular contents of the vesicles. Silverstein, et al., Annu. Rev. Biochem., Vol. 46, pp. 669-722 (1977); Simianescu, et al., J. Cell Biol., Vol. 64, pp. 586-607 (1975).
Many of the endocytotic vesicles are coated and are formed by invagination of coated regions of the plasma membrane called coated pits. Coated pits and vesicles provide a specialized pathway for taking up specific macromolecules from the extracellular fluid. This process is called receptor-mediated endocytosis. Goldstein et al., Nature, Vol. 279, pp. 679-685 (1979); Pearse, et al., Annu. Rev. Biochem., Vol. 50, pp. 85-101 (1981); Postan, et al., Annu. Rev. Physiol., Vol. 43, pp. 239-250 (1981). The macromolecules that bind to specific cell surface receptors are internalized via coated pits. Goldstein, supra. Receptor-mediated endocytosis is a selective mechanism enabling cells to ingest large amounts of specific ligands without taking in correspondingly large amounts of extra-cellular fluid. Goldstein, supra.
One such macromolecule is low density lipoprotein ("LDL"). Numerous studies have been performed involving LDL and the receptor-mediated endocytotic pathway. In addition to LDL, many other cell surface receptors have been discovered to be associated with coated pits and receptor-mediated endocytosis. Pastan et al., Annu. Rev. Physiol., Vol. 43, pp. 239-250 (1981). For example, studies have analyzed the hormone insulin binding to cell surface receptors and entering the cell via coated pits. Stryer et al., Biochemistry, Freeman & Co., New York (1988); Alberts et al., Molecular Biology of the Cell, Garland Publishing, New York (1983). In addition, it has been determined that some cell surface receptors associate with coated pits only after ligand binding. Pastan, supra.
Taking advantage of receptor-mediated endocytosis, the asialoglycoprotein receptor has been used in targeting DNA to HepG2 cells in vitro and liver cells in vivo. Wu et al., J. Biol. Chem., Vol. 262, pp. 4429-4432 (1987); Wu et al., Bio., Vol. 27, pp. 887-892 (1988); Wu et al., J. Biol. Chem., Vol. 263, pp. 14620-14624 (1988); Wu et al., J. Biol. Chem., Vol. 264, pp. 16985-16987 (1989); Wu et al., J. Biol. Chem., Vol. 266, pp. 14338-14342 (1991). These studies used asialoorosomucoid covalently linked to polylysine with water soluble carbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide or with 3'(2'pyridyldithio)propionic acid n-hydroxysuccinimide ester. Polylysine in the studies above bound DNA through ionic interaction. The DNA was ingested by endocytosis.
Other studies have utilized transferrin and the transferrin receptor for delivery of DNA to cells in vitro. Wagner et al., P.N.A.S., Vol. 87, pp. 3410-3414 (1990). These studies modified transferrin by covalently coupling transferrin to polylysine. Id. The polylysine interacted ionically with DNA. Delivery of DNA occurred to cells through the transferrin receptor. Such analyses were performed in vitro. Id. Cotten et al., P.N.A.S., Vol. 87, pp. 4033-4037 (1990); Zenk et al., P.N.A.S., Vol. 87, pp. 3655-3659 (1990).
In addition to DNA, macromolecules can also be delivered by receptor-ligand systems. Leamon et al., P.N.A.S., Vol. 88, pp. 5572-5576 (1991); Leamon et al., J. Biol. Chem., Vol. 267, pp. 24966-24971 (1992). In particular these studies have involved the folate receptor, an anchored glycosylphosphatidyl protein, which is excluded from coated pits and cycles in and out of the cells by caveolae. Anderson et al., Science, Vol. 252, pp. 410-411 (1992). This uptake mechanism has been called potocytosis. Id. Folate conjugated enzymes have been delivered into cells through this receptor system and retained activity for at least 6 hours. Leamon et al., P.N.A.S., Vol. 88, pp. 5572-5576 (1991). Folate receptors have limited tissue distribution and are overexpressed in several malignant cell lines derived from many tissues. Weitman et al., Cancer Res., Vol. 52, pp. 3396-3401 (1992); Weitman et al., Cancer Res., Vol. 52, pp. 6708-6711 (1992); Campbell, Cancer Res., Vol. 51, pp. 5329-5338 (1991); Coney, Cancer Res., Vol. 51, pp. 6125-6123 (1991). Other studies have also used biotin or folate conjugated to proteins by biotinylation for protein delivery to the cell. Low et al., U.S. Pat. No. 5,108,921.
DNA and macromolecule delivery is hindered by lysosomal degradation. Studies have analyzed the endosomal/lysosomal degradation process. It has been determined that organisms which are internalized via receptor-mediated endocytosis or receptor:ligand systems, like viruses and other microorganisms, escape lysosomal degradation in order to function. The entry mechanism of some viruses have been studies extensively. For some viruses outer membrane proteins have been demonstrated to be important for endosomal escape. Marsh et al., Adv. Virus Res., Vol. 36, pp. 107-151 (1989). Other studies have focused on methods to prevent lysosomal degradation. These studies have used substances which pertubate endosomal/lysosomal function. Mellmann et al., Ann. Rev. Biochem., Vol. 55, pp. 663-700 (1986). These substances have only been used in vitro. In addition, studies show that the entire virus-shell is necessary for efficient endosomal lysis. Marsh et al., Adv. Virus Res., Vol. 36, pp. 107-151 (1989). Studies have also demonstrated that adenovirus will enhance transferrin-polylysine mediated gene delivery. Curiel P.N.A.S., Vol. 88, pp. 8850-8854 (1991).
A number of bacteria are also internalized via receptor-mediated endocytosis and are liberated from the endosome by production of toxins. These toxins lyse the endosomal membrane. Moulder, Microbiol. Rev., Vol. 49, pp. 298-337 (1985). Listeria monocytogenes produce a membranolytic toxin called listeriolysin. Cossart et al., Mol. Biol. Med., Vol. 6, pp. 463-474 (1989); Tilney et al., J. Cell Bio., Vol. 109 pp. 1597-1608 (1989). Studies have shown that no other cofactors are needed for endosomal escape of Listeria monocytogenes. Bielecki et al., Nature Vol. 345 pp. 175-176 (1990).
The listeriolysin toxin forms pores in membranes which contain cholesterol. These pores are large enough for macromolecules like immunoglobulins to pass. Ahnert-Hilger et al., Mol. Cell Biol., Vol. 31 pp. 63-90 (1989); Geoffroy et al., J. of Bacteriol., Vol. 172, pp. 7301-7305 (1990).


A rocker arm arrangement for a valve drive of an internal combustion engine may include a roller shaft including at least one roll and an adjusting arrangement configured to adjust the roller shaft between a first position and a second position. The rocker arm arrangement may also include a first cam and a second cam respectively having a cam stroke region and an idle speed region and secured to a cam shaft. The adjusting arrangement may include a first engagement pin and a second engagement pin arranged on the roller shaft and adjustable into a switching position and into a home position. The first guide track and the second guide track may be respectively arranged on the cam shaft in a circumferential direction of the cam shaft at least partially overlapping one of the cam stroke region of the first cam and the cam stroke region of the second cam.

A rocker arm arrangement is used in a valve drive of an internal combustion engine in order to control valves. A rocker arm, which is connected to a valve, is rotatably mounted on a rocker arm axis for this purpose. A roller shaft comprising a rotatable roll is further secured to the rocker arm, which can be adjusted back and forth into a first position and into a second position. The roll is thus alternately connected to a first cam or to a second cam in a driving manner. The two cams are secured to a rotatable cam shaft and have profiles, which differ from one another in the circumferential direction, each comprising a cam stroke. If the roll is drivingly connected to the first cam, the roll follows the profile of the first cam, and the roller shaft as well as the rocker arm perform a stroke movement, which corresponds to the profile of the first cam. The roll, which is drivingly connected to the second cam, thus follows the profile of the second cam, and the roller shaft as well as the rocker arm perform a different stroke movement. The stroke motion sequence of the cylinder valve, which is secured to the rocker arm, can be changed in this way.
To connect the roll alternately to the first cam or to the second cam, two engagement pins are typically adjustably arranged in the roller shaft. In a switching position, the engagement pins can each interact with a guide track, by means of which the engagement pin and the roller shaft are shifted parallel to the rocker arm axis. The shifting of the roller shaft into the first and into the second position can thereby only take place when the two cams do not pass through a cam stroke on the roll. In addition, the respective engagement pin also has to be pushed out of the guide track into a home position after the adjustment of the roller shaft. As a result of the very short available time interval, the respective engagement pin is subjected to high acceleration and adjusting forces. The slide guides comprising the respective guide tracks are further also mechanically stressed to a high degree.


The wafer processing system includes a rotatable wafer support member for supporting a wafer and a plurality of collections trays disposed about a peripheral edge of the wafer support member. The collection trays are arranged in a stacked configuration, each collection tray having an inner wall portion and an outer wall portion that converge to define a trough section for collecting fluid. The system includes a chamber exhaust outlet that is formed in the housing for venting gas from the interior of the housing outside of the collection trays and a chemical exhaust outlet that is formed in the housing for venting gas that flows through the collection chamber to the chemical exhaust outlet. The chemical exhaust outlet is fluidly isolated from the chamber exhaust outlet.

This invention relates particularly to silicon wafer processing where multiple fluids are used during a process to clean, etch or do other wet process operations. The fluids are often expensive and it is desirable to reuse them to exhaustion.
Normal wafer processing employs one collection chamber to separate a special fluid from the waste drain and enable recirculation of the fluid.
The object of this invention is to have multiple, independent collection chambers, with the ability to separate multiple different fluids for recirculation and reuse.

Collection chamber apparatus to separate multiple fluids during the semiconductor wafer processing cycle


The preparation and use of particulate metallic solder alloy having particles of a single chemical composition is described. The particles of the particulate metallic solder alloy have a bimodal size distribution in which particles in a smaller size range have a largest dimension that is smaller than a smallest dimension of particles in a larger size range of the bimodal distribution. In some examples the particles in the smaller size mode have dimensions in the range of 1 to 100 nm. In some examples, the particles in the larger size mode have dimensions in the range of 2 to 75 microns in dimension. In some examples, a halogen-free flux is used. In some examples, a solvent is used to make a paste.

Solders and soldering techniques are widely used in electronics manufacturing, including electronics assembly and packaging. Solder paste is one of the main forms of solder materials used in industry to bond and assemble electronic components of various types into electronic devices or photonic devices. One main usage of solder paste is through a ball grid array (BGA) technique for surface mounting packaging. Solder paste is composed of two materials: solder balls (normally in the micron size) and solvents that are used to prepare the paste, which usually contains a flux that is used to clean the surface oxide of the solder balls to ensure complete solder reflow upon melting. The metallic solder balls are evenly dispersed in a paste flux that allows printing through stencil apertures that match substrate pad locations, and reflowing the printed assembly at elevated temperatures which melts and ultimately forms the joints and interconnects.
Traditionally, the most widely used solder material is eutectic tin-lead (Sn—Pb) alloy (63/37 wt %). Due to the toxicity and health concerns of lead, lead-based solders are being phased out of the electronics manufacturing processes. There have been many lead-free solder candidates, and the most widely used candidates include tin/silver/copper (Sn/Ag/Cu, also referred to as SAC), Sn/Ag, and Sn/Cu. In certain processes or products, complete replacement with lead-free solders has been achieved. However, for certain industries such as defense, aerospace and medical devices, many lead-free candidates cannot achieve the same quality as Sn—Pb solders and may lead to reliability issue. Thus these industries are currently exempted from the lead-based solders. Also, for many lead-free solders such as SAC solders, the melting points are around 220° C. or above (depending on compositions), which may lead to higher processing temperatures during electronics manufacturing and thus increased thermal stress on the circuit board. Another significant issue for lead-free solder materials is the formation of tin whiskers, which may lead to short circuits for the electronics devices.
With the electronics industry's focus on further miniaturization and push to the "nanoelectronics" era, nanosolders are expected to play a key role in assembling nano-components (nano-building blocks) into nanoelectronics and nanosystems due to several orders smaller of solder size and potential lower melting temperature, for example, MEMS (Microelectromechanical systems) packaging and microBGA packaging.
One prior art paper by H. Jiang et al, titled "Synthesis and Thermal and Wetting Properties of Tin/Silver Alloy Nanoparticles for Low Melting Point Lead-Free Solders," which was published in Chem. Mater. 2007, 19, 4482-4485, and appeared online on Aug. 11, 2007, is said to describe tin/silver alloy nanoparticles with various sizes that were synthesized via a low-temperature chemical reduction method, and their thermal properties were studied by differential scanning calorimetry. The particle size dependency of the melting temperature and the latent heat of fusion was observed. The melting point was achieved as low as 194° C. when the average diameter of the alloy nanoparticles was around 10 nm. The wetting test for as-prepared 64 nm (average diameter) SnAg alloy nanoparticle pastes on a Cu surface showed the typical Cu6Sn5 intermetallic compound (IMC) formation. These low melting point SnAg alloy nanoparticles could be used for low-temperature lead-free interconnect applications.
Also known in the prior art is Arvin et al., U.S. Patent Application Publication No. 2013/0284495 A1, published Oct. 31, 2013, which is said to disclose inert nano-sized particles having dimensions from 1 nm to 1,000 nm are added into a solder ball. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. The inert nano-sized particles may be a single compound, or may be a metallic material having a coating of a different material. In another embodiment of the present invention, a small quantity of at least one elemental metal that forms stable high melting intermetallic compound with tin is added to a solder ball. The added at least one elemental metal forms precipitates of intermetallic compounds with tin, which are dispersed as fine particles in the solder.
Also known in the prior art is Zinn, U.S. Pat. No. 8,834,747, issued Sep. 16, 2014, which is said to disclose compositions containing tin nanoparticles and electrically conductive particles. The tin nanoparticles can have a size below about 25 nm so as to make the compositions fusable at temperatures below that of bulk tin (m.p.=232° C.). Particularly, when the tin nanoparticles are less than about 10 nm in size, the compositions can have a fusion temperature of less than about 200° C. The compositions can contain a whisker suppressant to inhibit or substantially minimize the formation of tin whiskers after tin nanoparticle fusion. In some embodiments, the compositions contain tin nanoparticles, electrically conductive particles comprising copper particles, and a whisker suppressant comprising nickel particles. Methods for using the present compositions are also described herein. The compositions can be used as a lead solder replacement that allows rework to be performed.
There is a need for improved lead-free solders having relatively low processing temperatures.

Preparation and application of Pb-free nanosolder


A game apparatus comprising a game board adapted for horizontal disposition and having an upstanding backboard and a pair of sideboards extending upwardly from the game board. The backboard, and sideboards and the playing board all defining playing surfaces at which a plurality of quoits are physically thrown by a player from a remote position in attempt to land the quoit, by direct hit or by rebound, into a target cup recessed in and below the playing surface. The sideboards are each characterized by a sloped upper wall each sideboard define a frontal approach by the player to the playing board so as to encourage tossing of the quoits from the front or from the side, either by tossing the quoit, rebounding it or rolling it into the scoring cup.

1. Field of the Invention
The present invention is directed to games and more particularly to games of skill involving the tossing of playing pieces, in the form of quoits, discs or the like angularly or directly toward a playing board having a scoring cup recessed in the surface thereof.
Games of skill in which playing pieces are tossed towards a goal have long existed in the form of horseshoes, ring tosses and the like, tossed by players toward a stake. The games are adapted for either indoor or outdoor use although certain of them, such as horseshoes are commonly played only outdoors because of the size of the playing piece (the horseshoe) or the amount of space in which the game inherently must be played. Other games such as coin or quoit tosses may be played both indoor or outdoor in a room or on lawns, playgrounds, patios or similar areas. Although these various games historically may be played by persons of any age some are more commonly played by adults than by children, i.e., horseshoes. The present game may be played either indoor or out, by adults or by children and is conceived to provide enjoyment, challenge and competition, for all ages of players in a novel manner.


A shoulder pad assembly for contact sports such as hockey is described. Two separate shoulder assemblies, in the form of generally U-shaped shoulder bands, are each pivotally connected fore and aft to chest and back pieces. Preferably the pivotal connections are co-axial, so that there are just two pivot points, namely fore and aft pivot points centrally located on the chest and back pieces, thus generally defining a V-shape for the shoulder portions of the pad. Preferably, the flexibility is limited by the use of a pivot clip at each pivot point, the pivot clip having at least one post disposed from the pivot axis and projecting from the clip through an arcuate slot in each shoulder band, the arcuate slots being of finite length such that further pivoting is prevented once the post reaches an end of the slot.

1. Field of the Invention
This invention relates to shoulder pads for use as protective gear in contact sports, especially hockey.
For convenience, reference will be made to hockey in particular throughout this description, but it should be clearly understood that that is by no means intended to be limiting. The principle of the invention may also be employed in football, or in any other contact sport where shoulder protection is required or desired.
2. Description of the Prior Art
In hockey, shoulder pads in the prior art have generally have limited flexibility, most commonly comprising a vest-like structure, or separate chest and back pieces, with shoulder and upper arm protective pads attached thereto.
Generally, when a player lifts one shoulder, the entire shoulder pad assembly shifts, including the vest structure, or chest and back pieces, and the opposite shoulder protection. The need to so displace the entire assembly necessarily means that more force is required than would otherwise be the case. It follows that the player's movement is more restricted than would otherwise be the case; the player has to exert more force to move, since he is forced to displace the entire assembly.
Furthermore, because the entire assembly has to shift, the pads tend to "ride up", thus potentially exposing portions of the upper body to injury.

Shoulder pad assembly for contact sports


The present invention relates to an expression system for anaerobic gene expression in higher plants. The expression system comprises the promoter GapC4 or a fragment or variant and a gene to be expressed. A concrete field of application of the present invention is agriculture, particularly resistance cultivation.

The loss of harvested crops, which results from diseases of plants, represents a world-wide problem. For example, potatoes suffering from potato wet rot or potato rot (rotting of the tuber) and black leg or black stem (rotting of the lower stem sections) after infection by the phytopathogenic bacterium Erwinia carotovora, results in crop losses to an estimated amount of 100 million dollars world-wide (Perombelon et al., 1980, Ann. Rev. Phytopathol. 18: 361-387). There is a number of studies dealing with the transmission of resistance factors to plants by means of genetic engineering (Lamb et al., 1992, Bio/Technology 10: 1436-1445; Hain et al., 1994, Current Opinion in Biotechnology, 125-130; Zhu et al., 1994, Bio/Technology 12: 807-812). In order to increase the resistance of potatoes to Erwinia carotovora, the T4 lysozyme gene of the bacteriophage T4 was expressed in transgenic potatoes (During et al., 1993, Plant J. 3: 587-598).
However, since bacterial diseases of plants often spread under anaerobic conditions, the resistance factors for plants transmitted so far, are effective only in a very restricted extent. This applies particularly to the above-mentioned disease of potatoes suffering from potato rot and black leg, since the infection caused by Erwinia carotovora takes place predominantly under anaerobic conditions. This effect is increased by the formation of a mucus from bacteria and degradation products of vegetable cell membranes. Regarding an effective expression of an antibacterial protein under optimum conditions, it is desirable to control the corresponding foreign gene by a promoter active under these conditions.
Three anaerobic promoters have been tested in transgenic plants so far. These are the Adh1 promoter from corn, the Adh promoter from Arabidopsis thaliana and the GapC promoter from Arabidopsis thaliana. The Adh1 promoter from corn was investigated in tobacco and rice (Ellis et al., 1987, EMBO J. 6: 11-16; Kyozuka et al., 1991, Mol. Gen. Genet. 228: 40-48). The GapC promoter from Arabidopsis was investigated in tobacco (Yang et al., 1993, Plant Physiol. 101: 209-210), and the Adh promoter from Arabidopsis was investigated in Arabidopsis as such (Dolferus et al., 1994, Plant Physiol. 105: 1075-1087). It turned out that all promoters convey only 2 to 81 times the induction of the reporter gene over the background and are not active in all of the tissues.

Expression system for anaerobic gene expression in higher plants

MPG Cologne GmbH Molecular Plant & Protein Biotechnology


In the production of a silicon nitride sintered body through a hot press method, a sintering aid protecting agent is added to the raw material. The employable protecting agents are metallic elements such as Ta, W and Mo and compounds of the metallic elements such as nitrides and silicides. Conversion of these elements and compounds to carbides occurs preferentially to reduction of the sintering aid. Thus, it becomes possible to suppress reduction of the sintering aid in a reducing atmosphere formed, for example, of carbon monoxide, which is generated particularly when a graphite pressing die is employed.

1. Field of the Invention
The present invention relates to a silicon nitride sintered body; a process for producing the same; a ceramic heater employing the silicon nitride sintered body serving as a substrate; and a glow plug containing the ceramic heater. More particularly, the present invention relates to a silicon nitride sintered body which can suppress reduction of a sintering aid such as silicon oxide occurring in a reducing atmosphere formed by a carbonaceous component during firing, and which sintered body has consistent qualities such as excellent bending strength without variation and is sufficiently densified through to the surface, and to a process for producing the sintered body. The present invention also relates to a ceramic heater employing the silicon nitride sintered body, which heater can be utilized for a variety of uses and whose properties such as mechanical strength and electrical resistance demonstrate negligible variation, and to a glow plug containing the ceramic heater serving as a heat source and employable in diesel engines.
2. Description of Related Art
Silicon nitride is sintered by the action of a liquid phase formed from a sintering aid during heating. The melting point of the formed liquid phase is known to vary in relation to the compositional ratio between a main sintering aid such as MgO, Al2O3xe2x80x94Y2O3, or RE2O3 (RE: rare earth element) and SiO2, which serves as an additional sintering aid and is contained in silicon nitride raw material. The sinterability is greatly affected by variations in the melting point, thereby varying the quality of the produced sintered body.
When a silicon nitride sintered body is produced through hot pressing, a pressing die made of graphite is typically employed, thereby providing a reducing atmosphere for firing. Therefore, an oxide sintering aid, particularly silicon oxide partially undergoes reduction, and the compositional proportions of sintering aids vary. As a result, sinterability is greatly affected as described above, and sintered bodies having consistent physical properties are difficult to produce, because of intra-lot and inter-lot variations in quality of the produced sintered bodies. In addition, since a portion of the raw material in the vicinity of the pressing die is insufficiently sintered, a silicon nitride sintered body fully densified through to the surface may not be produced.
The present invention has been made to solve the aforementioned problems. The silicon nitride sintered body of the first aspect of the invention contains a carbide which is converted from a sintering aid protecting agent (hereinafter referred to as a xe2x80x9cprotecting agentxe2x80x9d) which prevents reduction of a sintering aid due to a carbonaceous component contained in a reducing atmosphere during hot press firing.
As described in the second aspect of the invention, examples of protecting agents having a high melting point include at least one species from among Ta, W, Mo and compounds thereof. Of these, elements, nitrides, and silicides, such as W, TaN and MoSi2, which are readily converted to carbides thereof in a reducing atmosphere, are preferable.
As described in the third aspect of the invention, the sintering aid contains silicon oxide and the protecting agent contains a metal and/or metallic compound which can be converted to carbide more easily than silicon oxide.
As described in the fourth aspect of the invention, sintering aids including a rare earth element oxide and silicon oxide are employed and reduction of the sintering aids is sufficiently prevented, thereby efficiently producing a silicon nitride sintered body having a grain boundary phase containing RE2SiO5 and/or RE2Si2O7.
In the fifth aspect of the invention, there is provided a process for producing a silicon nitride sintered body, which process comprises obtaining a compact from a material containing silicon nitride raw material powder, sintering aid powder and a protecting agent; placing the compact in a pressing die; placing the pressing die holding the compact in a firing furnace and hot press firing.
In the sixth aspect of the invention, there is provided a ceramic heater containing a substrate and a resistance heater, wherein the substrate is formed of a silicon nitride sintered body as recited in any one of the first to fourth aspects of the invention.
The seventh aspect of the invention comprehends a glow plug containing a ceramic heater as recited in the sixth aspect of the invention.
Accordingly, it is an object of the present invention to provide a silicon nitride sintered body which can suppress reduction of a sintering aid occurring when a firing atmosphere becomes a reducing atmosphere due to a carbonaceous component, particularly when a pressing die formed of graphite is used, and which silicon nitride sintered body has consistent qualities such as excellent bending strength without variation and is sufficiently densified through to the surface.
Another object of the present invention is to provide a process for producing the sintered body.
Still another object of the present invention is to provide a ceramic heater which employs the silicon nitride sintered body as a substrate and which has reduced variation in properties such as mechanical strength and electrical resistance.
Yet another object of the present invention is to provide a glow plug containing the ceramic heater as a heat source.

Process for producing silicon nitride sintered body for use in ceramic heater for use in glow plug


An easily mountable and removable rack for carrying long items such as surfboards and the like on a vehicle. The inventive device includes a first main portion positionable between a window of the vehicle and an adjoining vehicle door panel. A second substantially U-shaped main portion is adjustably coupled to the first main portion and is operable to receive a load to support the same relative to the vehicle. Preferably, the device is utilized in pairs to support elongated objects along the length of the vehicle.

1. Field of the Invention
The present invention relates to vehicle racks and more particularly pertains to such racks which are mounted on the side of a vehicle.
2. Description of the Prior Art
The use of side mounted vehicle racks is known in the prior art. More specifically, racks heretofore devised and utilized for the purpose of side mounting on vehicles are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
More specifically, such prior art racks have frequently been mounted by hooks engaging inside the hood and trunk portion of vehicles as illustrated by U.S. Pat. Nos. 4,596,348; 4,108,342; and 5,029,785. Due to the provision of internal channels or gutters of varying configurations within the hoods and trunks of vehicles, such racks frequently need to be customized for a particular vehicle and in any event require adjustment of the portions designed to fasten within such hood and trunk. Other racks have been designed to enter open vehicle windows and hoods thereover, e.g. U.S. Pat. Nos. 4,942,989 and 4,607,773, creating an obvious problem in case of rain. Sliding between the window glass and its associated weatherstripping attached to the car body as does the rack of the present invention obviates these problems and, since the clearance is essentially the same for all vehicles, the rack of the present invention is universal in its installation.
In this respect, the side mounted rack according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of ease and universality of use.
Therefore, it can be appreciated that there exists a continuing need for new and improved racks which can be side mounted on a vehicle. In this regard, the present invention substantially fulfills this need.


A system for synthesizing a speech signal from strings of words, which are themselves strings of characters, includes a memory in which predetermined syntax tags are stored in association with entered words and phonetic transcriptions are stored in association with the syntax tags. A parser accesses the memory and groups the syntax tags of the entered words into phrases according to a first set of predetermined grammatical rules relating the syntax tags to one another. The parser also verifies the conformance of sequences of the phrases to a second set of predetermined grammatical rules relating the phrases to one another. The system retrieves the phonetic transcriptions associated with the syntax tags that were grouped into phrases conforming to the second set of rules, and also translates predetermined strings of characters into words. The system generates strings of phonetic transcriptions and prosody markers corresponding to respective strings of the words, and adds markers for rhythm and stress to the strings, which are then converted into data arrays having prosody information on a diphone-by-diphone basis. Predetermined diphone waveforms are retrieved from memory that correspond to the entered words, and these retrieved waveforms are adjusted based on the prosody information in the arrays. The adjusted diphone waveforms, which may also be adjusted for coarticulation, are then concatenated to form the speech signal. Methods in a digital computer are also disclosed.

The present invention relates to methods and apparatus for synthesizing speech from text.
A wide variety of electronic systems that convert text to speech sounds are known in the art. Usually the text is supplied in an electrical digitally coded format, such as ASCII, but in principle it does not matter how the text is initially presented. Every text-to-speech (TTS) system, however, must convert the input text to a phonetic representation, or pronunciation, that is then converted into sound. Thus, a TTS system can be characterized as a transducer between representations of the text. Much effort has been expended to make the output of TTS systems sound "more natural" viz more like speech from a human and less like sound from a machine.
A very simple system might use merely a fixed dictionary of word-to-phonetic entries. Such a dictionary would have to be very large in order to handle a sufficiently large number of words, and a high-speed processor would be necessary to locate and retrieve entries from the dictionary with sufficiently high speed.
To help avoid such drawbacks, other systems, such as that described in U.S. Pat. No. 4,685,135 to Lin et al., use a set of rules for conversion of words to phonetics. In the Lin system, phonetics-to-sound conversion is accomplished with allophones and linear predictive coding (LPC), and stress marks must be added by hand in the input text stream. Unfortunately, a system using a simplistic set of rules for converting words to phonetic representations will inevitably produce erroneous pronunciations for some words because many languages, including English, have no simple relationship between orthography and pronunciation. For example, the orthography, or spelling, of the English words "tough", "though", and "through" bears little relation to their pronunciation.
Accordingly, some systems, such as that described in U.S. Pat. No. 4,692,941 to Jacks et al., convert orthography to phonemes by first examining a keyword dictionary (giving pronouns, articles, etc.) to determine basic sentence structure, then checking an exception dictionary for common words that fail to follow the rules, and then reverting to the rules for words not found in the exception dictionary. In the system described in the Jacks et al. patent, the phonemes are converted to sound using a time-domain technique that permits manipulation of pitch. The patent suggests that inflection, speech and pause data can be determined from the keyword information according to standard rules of grammar, but those methods and rules are not provided, although the patent mentions a method of raising the pitch of words followed by question marks and lowering the pitch of words followed by a periods.
Another prior TTS system is described in U.S. Pat. No. 4,979,216 to Malsheen et al., which uses rules for conversion to phonetics and a large exception dictionary of 3000-5000 words. The basic sound unit is the phoneme or allophone, and parameters are stored as formants.
Such systems inevitably produce erroneous pronunciations because many languages have words, or character strings, that have several pronunciations depending on the grammatical roles the strings play in the text. For example, the English strings "record" and "invalid" both have two pronunciations in phrases such as "to record a new record" and "the invalid's invalid check".
In dealing with such problems, most prior TTS systems either avoid or treat secondarily the problem of varying the stress of output syllables. A TTS system could ignore stress variations, but the result would probably be unintelligible as well as sound unnatural. Some systems, such as that described in the Lin patent cited above, require that stress markers be inserted in the text by outside means: a laborious process that defeats many of the purposes of a TTS system.
"Stress" refers to the perceived relative force with which a sound, syllable, or word is uttered, and the pattern of stresses in a sequence of words is a highly complicated function of the physical parameters of frequency, amplitude, and duration. "Orthography" refers to the system of spelling used to represent spoken language.
In contrast to the approaches of prior TTS systems, it is believed that the accuracy of stress patterns can be even more important than the accuracy of phonetics. To achieve stress pattern accuracy, however, a TTS system must take into account that stress patterns also depend on grammatical role. For example, the English character strings "address", "export", and "permit" have different stress patterns depending on whether they are used as nouns or verbs. Applicant's TTS system considers stress (and phonetic accuracy in the presence of orthographic irregularities) to be so important that it uses a large dictionary and a natural-language parser, which determines the grammatical role each word plays in the sentence and then selects the pronunciation that corresponds to that grammatical role.
It should be appreciated that Applicant's system does more than merely make an exception dictionary larger; the presence of the grammatical information in the dictionary and the use of the parser result in a system that is fundamentally different from prior TTS systems. Applicant's approach guarantees that the basic glue of English is handled correctly in lexical stress and in phonetics, even in cases that would be ambiguous without the parser. The parser also provides information on sentence structure that is important for providing the correct intonation on phrases and clauses, i.e., for extending intonation and stress beyond individual words, to produce the correct rhythm of English sentences. The parser in Applicant's system enhances the accuracy of the stress variations in the speech produced among other reasons because it permits identification of clause boundaries, even of embedded clauses that are not delimited by punctuation marks.
Applicant's approach is extensible to all languages having a written form in a way that rule-based text-to-phonetics converters are not. For a language like Chinese, in which the orthography bears no relation to the phonetics, this is the only option. Also for languages like Hebrew or Arabic, in which the written form is only "marginally" phonetic (due, in those two cases, to the absence of vowels in most text), the combination of dictionary and natural-language parser can resolve the ambiguities in the text and provide accurate output speech.
Applicant's approach also offers advantages for languages (e.g., Russian, Spanish, and Italian) that may be superficially amenable to rule-based conversion (i.e., where rules might "work better" than for English because the orthography corresponds more closely to the phonetics). For such languages, the combination of a dictionary and parser still provides the information on sentence structure that is critical to the production of correct intonational patterns beyond the simple word level. Also for languages having unpredictable stress (e.g., Russian, English, and German), the dictionary itself (or the combination of dictionary and parser) resolves the stress patterns in a way that a set of rules cannot.
Most prior systems do not use a full dictionary because of the memory required; the Lin et al. patent suggests that a dictionary of English words requires 600 K bytes of RAM. Applicant's dictionary with phonetic and grammatical information requires only about 175 K bytes. Also, it is often assumed that a natural-language parser of English would be too time consuming for practical systems.
This invention is an innovative approach to the problem of text-to-speech synthesis, and can be implemented using only the minimal processing power available on MACINTOSH-type computers available from Apple Computer Corp. The present TTS system is flexible enough to adapt to any language, including languages such as English for which the relationship between orthography and phonetics is highly irregular. It will be appreciated that the present TTS system, which has been configured to run on Motorola M68000 and Intel 80386SX processors, can be implemented with any processor, and has increased phonetic and stress accuracy compared to other systems.
Applicant's invention incorporates a parser for a limited context-free grammar (as contrasted with finite-state grammars) that is described in Applicant's commonly assigned U.S. Pat. No. 4,994,966 for "System and Method for Natural Language Parsing by Initiating Processing prior to Entry of Complete Sentences" (hereinafter "the '966 patent"), which is hereby incorporated in this application by reference. It will be understood that the present invention is not limited in language or size of vocabulary; since only three or four bytes are needed for each word, adequate memory capacity is usually not a significant concern in current small computer systems.

Method and apparatus for speech synthesis based on prosodic analysis


A multi-piston, ratcheted dispensing device for cosmetic and pharmaceutical formulations comprising a hollow body, the body being interiorly divided into at least two channels; a ratchet cup for applying force to at least two ratcheting members, each ratcheting member being in rigid contact with one of at least two pistons, each piston being disposed within the channels; at least one recoil member for biasing the ratchet cup away from the pistons; exit orifices disposed within the body; and, optionally, conductors for directing the dispensed product, sealing mechanisms to prevent dry-out of the product and an actuator.

New cosmetic formulations are increasingly viscous or contain solid components that are difficult or impossible to dispense using existing technology. Simultaneously, there exists a growing demand for cosmetic formulations with physiologically active components. But such components are often unstable in consumer products.
One response to the first problem has been to design mechanical pump dispensers that can handle today's more viscous products. To date, the results have not been encouraging. Mechanical micropumps can be of the traditional or so-called "airless" types, and are well known. See, for example, U.S. Pat. Nos. 3,001,524; 3,452,905; 4,892,232; 4,9303,999; 5,096,097; 5,183,187; 5,566,865.
One type of piston dispenser relies on an airless micropump mechanism to force flowable material out of a reservoir. On the return stroke of the pump mechanism a vacuum is created inside the reservoir. In response to the reduced pressure inside the reservoir, flowable material from the primary container moves into the reservoir, and simultaneously, the piston is pulled toward the reservoir, thus reducing the volume between the piston and the intake of the reservoir. With this type of device, and in the traditional non-airless pumps, only comparatively thin products can be made to flow because insufficient negative pressure is created inside the reservoir.
Furthermore, micropumps, because of the several small and delicate components of which they are comprised, are subject to failure of various types. The most common of these, perhaps, is leakage. Commonly, leakage may occur through the stem of the pump as a result of poor fit between the piston and the stem. Leakage may also occur from around the stem of the pump as a result of poor fit between the piston and the housing.
Poor fit between the components may be a result of the difficulties of holding to tolerance in manufacturing or it may be due to creep of the molded components before reaching a final set after manufacturing. Poor fit of the components may also be due to degradation of the components as a result of exposure to various elements, i.e. heat, cold, and chemical attack by the product.
In another piston-type dispensing device, a relatively high pressure region is located behind the piston. When the exit valve for the product is opened, the piston is driven by the pressure gradient and product is forced out of the open valve.
The primary disadvantages here are the hazards of manufacturing, transporting, storing, using and disposing of pressurized containers. Because of these hazards there are also limitations on the container materials and construction.
Furthermore, performance characteristics may suffer with this type of package. Specifically, as the pressure inside the container decreases with use, the dispensing characteristics deteriorate. Toward the end of the life of the package, product is dispensed slowly and weakly, creating an unfavorable impression on the consumer. Sometimes all of the pressure will be lost before the contents of the package are used up. Also, this type of package is subject to leaking as a result of constant pressure on the sealing surfaces of the package.
Other piston-type dispensers rely on mechanical pressure applied directly or indirectly to the piston. U.S. Pat. No. 5,513,778 discloses a dispenser for viscous fluid products that is operated by applying direct manual pressure to the piston, which is accessible through an opening on the bottom of the outer body. French Patent No. 2,721,907 discloses a cosmetic product dispenser for cream products in which the piston rides on a screw-threaded shaft when the shaft is rotated. This is an example of a piston that is activated by indirect pressure.
The '778 design is simple with few interrelated parts. Its disadvantages include the following: it requires two hands to operate; the piston disappears into the package making it inconvenient to apply pressure to the bottom of the piston; the force applied to the piston can result in the uncontrolled movement of the piston when static friction is suddenly overcome, resulting in a excessive dosing.
Dispensers that use indirect pressure such as the '907 design, are more complicated because a means of engagement must be supplied to transfer the applied pressure through the package to the piston. This increased complexity in design is disadvantageous in manufacturing, cost and use. This design also requires two hands to operate.
In response to the second problem, systems have been devised that allow the active components to be stored separately from the rest of the formulation. The consumer could then mix the components just prior to use. This system relies on the consumer mixing the components and doing so in the right proportions. More user friendly systems have the components mix just prior to, or upon exiting the container.
In such a typical configuration, two micropump devices or two pre-pressurized devices are ganged together and actuated by one actuator that fits over both valve stems. In practice, the results have not been satisfactory. In part, this is because of variations in the dispensed quantity from mechanism to mechanism. In the best cases, variations in a sample of like components dispensing the same product will be about 20%. Often the difference is greater. This means that unequal quantities of the two products are being dispensed.
Furthermore, this type of multi-dispenser does not perform well if the viscosities of the different products vary widely. The same micropump will have different dispensing characteristics for products with different theological properties, say, viscosity. This introduces additional variation in the relative quantity of the simultaneously dispensed products. This problem is made worse by uneven application of pressure on the actuator. If pressure is not transferred evenly to each valve stem, then each piston will not move the same distance, causing unequal dispensing of the two products.
Uneven use-up of the products is a serious drawback for at least two reasons. Firstly, the products were meant to be used together, but since one product will be used up before the other this becomes impossible. But even before any one of the products has been used up, the relative amount of each product in any one application will vary widely. In some cases this will render the combined product ineffective or give undesirable results. This is particularly true in treatments where one product activates the other or a desired reaction of the dispensed products is sought.
Another multi-dispenser is disclosed in French Patent No. 2,721,907. Here, a single composite piston fits into a double-barreled container, and advances along both barrels via a screw-threaded rotating shaft to dispense the products. This design is comparatively complex, involving a screw-threaded mechanism, requires two hands to operate, and is limited to two separate product components.
U.S. Pat. No. 5,076,298 discloses a dispenser for multi-component hair cosmetics in which separately stored product components are transferred by capillary action, from their separate containers and into tines made of absorbent material, where the components mix, just prior to use. This design, relying as it does on capillary activity, is suitable only for thin, non-viscous products.
There is then, a growing demand in the personal care markets for a device that can reliably dispense multiple components in any desired ratio of volume, keeping the components separated until just prior to use. Also, a reliable dispensing device is needed for simultaneously dispensing multiple components when the viscosities of the multiple components are significantly different from each other. Furthermore, a device that can reliably dispense products of relatively high viscosity is needed.
None of the limitations discussed above is found in the present invention. The present invention does not rely on pre-pressurized contents. Nor does the present invention rely on small, delicate components to create fluid movement indirectly via a vacuum. There are no small, delicate parts susceptible to the kinds of failure discussed above. The number of parts is comparatively few. There is only one type of sealing interface which means that only one fitment requires precise tolerance. The present invention can be operated with one hand. The pressure surface does not disappear into the package making it difficult to dispense product. No accidental excessive dosing, nor uneven dosing is possible. More than two components may be separated prior to use. The device may be designed to dispense different predetermined quantities of the different products, thus ensuring the correct proportions of each product.
Some of the limitations just noted are avoided by using a ratchet design. This design allows for dosing a prefixed amount of product, prevents excessive dosing by providing a positive stop, and returns the pressure surface to its initial position for subsequent uses. There are many ratcheting dispensers with diverse mechanisms of operation. Many involve numerous pins, springs, clamps and support racks. None meets the criteria of being simple in design, containing few parts, and using a single ratchet support column to simultaneously dispense multiple products.
Accordingly, a main object of the invention is to provide an improved multi-dispenser which overcomes the disadvantages of known multi-dispensing devices, having simplified construction and being convenient to use.
Another object of the present invention is to provide an improved dispensing device that can simultaneously dispense two or more materials whose viscosities differ from one another significantly.
Another object of the present invention is to provide an improved dispensing device that can simultaneously dispense different predetermined quantities of two or more materials.
Another object of the present invention is to provide an improved dispensing device that can dispense a measured amount of materials of relatively high viscosity.

Multi-piston, ratcheted dispensing device


A phase-change hydraulic fracturing process, including the following steps: (1) injecting clean water or conventional fracturing fluid to a formation, so that the formation fractures; (2) placing non-phase-change liquid and phase-change liquid in different liquid mixing tanks and injecting into a shaft at the same time, an injection volume ratio of the non-phase-change liquid to the phase-change liquid is (0-0.7):(0.3-1); (3) injecting a displacement fluid into the shaft, so that the non-phase-change liquid and the phase-change liquid in the shaft completely enter a reservoir; (4) performing well shut-in and pressure-out for 30-200 min, so that solid-phase matters generated by the phase-change liquid are laid in the fracture; and (5) relieving pressure to finish the construction.

The hydraulic fracturing technology has been widely used in the development of low-permeability oil and gas fields as a major measure for increasing production of oil and gas wells and augmented injection of water wells, and has made important contributions to stable production of oil and gas fields. The hydraulic fracturing process refers to pumping high-viscosity pre-flush fluid into a target reservoir, forming fractures at high pressure and extending the fractures, and then pumping sand-carrying fluid mixed with a proppant, wherein the sand-carrying fluid can continue to extend the fractures, and at the same time carry the proppant deep into the fractures; and finally, enabling the fracturing fluid to break and degrade into low-viscosity fluid which then flow to the bottom of the well and later flows back, thereby leaving a flow channel with high conductivity formed by the proppant supporting the fracture wall in the formation to facilitate flowing of oil and gas from the far-field formation to the bottom of the well.
Since the 1st hydraulic fracturing in the United States in 1947, after more than 60 years of development, the hydraulic fracturing technology has achieved an amazing development from theoretical research to field practice. For example, a fracture extending model has developed from two-dimension to pseudo-three-dimension and full three-dimension; a dynamic prediction model of a fractured well has developed from an electric simulation chart and a steady state flow model to a three-dimensional and three-phase unsteady model; the fracturing fluid has developed from crude oil and clean water to low-, medium-, and high-temperature series of high-quality, low-damage, delayed-crosslinking guar gum organoboron "double-variable" fracturing fluid systems and clean fracturing fluid systems; a proppant has developed from natural quartz sand to medium- and high-strength man-made ceramsites; fracturing equipment has developed from a low-power cement truck to a 1000, 2000, or 2500 fracturing truck; the single-well fracturing construction has developed from small-scale, low sand-to-liquid ratio to ultra-large, high-sand-fluid ratio fracturing operations; the field of fracturing applications has developed from specific low-permeability oil and gas reservoirs to simultaneous development of ultra-low-permeability and medium- and high-permeability oil and gas reservoirs (and sometimes sand-control fracturing).
However, from the point of view of the hydraulic fracturing technology and its development, all fracturing technologies are currently based on the process of forming fractures with a fracturing fluid, then injecting a solid proppant to hydraulic fractures, and supporting the fractures to keep them open, thereby obtaining a flow channel with high conductivity.
In 2010, Schlumberger proposed that the fracture conductivity in a HIWAY high-speed channel was not affected by the permeability of a proppant, and oil and gas do not pass through a proppant pack but instead flows through a high-conductivity channel. However, its implementation requires strict requirements on a perforating process, a pump injection process, and pump injection equipment. The construction cost is high and the process is complicated. It is also necessary to inject a proppant into the formation to open fractures.
The conventional guar gum fracturing fluid system and sand fracturing generally have the following problems:
(1) if the fracturing fluid is not thoroughly broken and returned, it will seriously injure the conductivity of artificial fractures and reduce the matrix permeability near the fractures;
(2) with respect to high temperature deep wells, in order to maintain the sand carrying capacity of the fracturing fluid at high temperature, the concentration of additives such as guar gum and crosslinker is increased, resulting in further increase of the residue content, further increase of frictional resistance, and further occurrence of the problems, such as gum breakage and flowback;
(3) for sand fracturing, in order to pursue high conductivity, sand is introduced at a high sand ratio, which can easily lead to sand plugging and other accidents;
(4) with the increase of production time after construction, problems such as embedding, deformation, and backflow of conventional proppants such as ceramsite and quartz sand will result in a significant decrease in post-pressure conductivity, and the construction validity will be greatly shortened.
The above problems often lead to a significant reduction in fracture conductivity. Therefore, the fracture permeability measured after post-pressure well testing can only reach one-tenth or even one-hundredth of the permeability in a laboratory.
In order to effectively improve the post-pressure permeability, reduce the reservoir damage caused by the fracturing fluid, and improve the overall fracturing effect, the present invention proposes a phase-change hydraulic fracturing process in which a phase-change fracturing fluid forms a solid support by means of its own phase-change, and a non-phase-change fracturing fluid injected together with the phase-change fracturing fluid flows back after the fracturing is completed to keep out of the space within the fracture to form an oil and gas seepage flow, such that the fracture permeability is greatly improved.

Phase-change hydraulic fracturing process


Certain embodiments of the present invention provide a system for clinical review of a patient comprising: a plurality medical studies relating to a medical history of the patient, each of said plurality of medical studies comprising a representation; a user interface for permitting a user to interact with said representations; a chronology of said representations displayable through said user interface, wherein each of said representations is selectable by said user to form a selected chronological medical study; and a plurality of relevant representations displayable through said user interface, said plurality of relevant representations automatically generated based at least in part on said selected chronological medical study and at least one relevance criterion, wherein each of said plurality of relevant representations is selectable to form a selected relevant medical study. In an embodiment, the system further comprises at least one thumbnail image displayed in said user interface, said at least one thumbnail image corresponding to a series of images in said selected relevant medical study, wherein said at least one thumbnail image is selectable to display said series of images in said selected relevant medical study.

Embodiments of the present application relate generally to dynamic display of clinical information through a user interface. Particularly, certain embodiments relate to chronological and relevant displays of medical studies in an intuitive and fluid manner.
When reviewing a patient's medical history, a reviewing clinician is faced with managing a potentially large amount of information. It should be understood that a patient's medical history may also include presently generated studies that are in a condition for clinical review. For a given patient, there may be studies spannig over a period of months or years. The studies may cover a variety of conditions and/or body parts. The studies may pertain to various clinical areas—e.g., radiology, cardiology, laboratory exams, neurology, pathology, oncology, etc. For radiology and other medical imaging applications, the studies may be generated through various modalities—e.g., CT scan, fluoroscopy, tomography, ultrasound, MRI, etc.
Furthermore, there may be layers of information for each study—e.g., various levels of information such as metadata, high-level study information, and underlying study data. The underlying data may also be stored in a variety of forms—e.g., linked database information, images, movies, text, etc. Given the potentially vast and diverse amount of information for any given patient, a reviewing clinician is faced with a difficult task.
The various patient studies, as a group may be considered horizontal patient information. For a given study, the various layers of information may be considered vertical information.
For a given patient review, a clinician may have to select among the horizontal patient information to efficiently access relevant patient studies. Further, the clinician may desire to efficiently "drill-down" through the vertical layers of a given patient study. It may be inefficient to provide a work-flow for the clinician that requires the manual integration of various data sources, data management applications, and data monitoring scenarios.
Thus, there is a need for efficient management of clinical patient information. There is a need for the ability for a clinician to intuitively browse, select, and review the horizontal and vertical patient information. Furthermore, there is a need for the clinician to manage in an integrated manner, both horizontally and vertically, the patient history information.

Integrated and intuitive display of clinical information


The structured document management apparatus includes a document data accepting unit that accepts input of structured document data having a hierarchical logic structure; a structure guide data storage unit that stores structure guide data which is a summary of hierarchical structure information of the structured document data; a structure stream converting unit that syntax-analyzes the accepted structured document data, and converts the structure information in the structured document data into structure stream data as one-dimensional sequence data using the structure guide data; and a structure stream data storage unit that stores the converted structure stream data.

1. Field of the Invention
The present invention relates to an apparatus, a program product and a method for structured document management that store and search for structured document data having a hierarchical logic structure.
2. Description of the Related Art
Some systems are considered as structured document management systems that store and search for structured document data described by XML (Extensible Markup Language) or the like.
The first system is a system that manages structured document data directly as a text file. The first system has a problem such that when the number and size of data become large, storage efficiency is deteriorated. Also, in the first system, a search utilizing the properties of the structured documents becomes difficult.
The second system is a system that manages structured document data in an RDB (Relational Database). The second system is widely used in backbone systems or the like.
The third system is a system that manages structured document data using an OODB (Object Oriented Database) which is developed for managing structured document data. The third system is, for example, an XML-compliant RDB where the RDB is extended.
Since the RDB stores data therein in a format of a flat table, complicated mapping which relates a hierarchical structure of XML data with a table is necessary. Due to the mapping, the performance is deteriorated if an advance structure (schema) relating to a table is not designed sufficiently.
In recent years, therefore, the fourth system which is an alternative to the first to third systems is proposed. The fourth system is a system that manages structured document data natively. In the fourth system, since XML data having various hierarchical structures are stored without executing a special mapping process, a special overhead is not preset at the time of storage and acquisition. Also, a costly advance schema design is not necessary, and thus the structure of the XML data can be changed freely according to a change in business environments.
Even when structured document data are stored efficiently, it does not make much sense if a means that fetches the stored data is not provided. As the means that fetches the stored data, a query language is used. As SQL (structured Query Language) is used in the RDB world, XQuery (XML Query Language) is established in XML. XQuery is a language for treating XML data like a database, and provides a means that fetches, aggregates and analyzes a data aggregate which matches to the predetermined conditions.
Since the XML data is described in a hierarchical structure where parentage and sibling elements are combined, a means that traces this hierarchical structure is provided. A technique for searching for structured document data including specific elements and a specific structure specified by search conditions while tracing the hierarchical structure of the structured document data stored in such a manner is disclosed, for example, in JP-A 2001-034618 and 2000-057163 (Kokai).
Since the XML data have the hierarchical structure where the parentage and sibling elements are combined, however, the storage efficiency is low.
As the structure of structured document data becomes larger, the number of structured document data stored in a database is larger or the search conditions are more complicated, it takes a longer time to execute the process for tracing between elements composing the hierarchical structures of the respective structured document data. When the number or size of structured document data becomes larger, the stored structured document data cannot be developed on a memory, and the most of them are stored in a secondary storage such as a hard disk.
Particularly, in the system that manages structured document data natively, the structured document data are stored with the hierarchical structure between the elements being unchanged. For this reason, the elements of the structured document data stored on the secondary storage should be frequently accessed in order to check whether a specified element or structure is present as the search condition. In the case of a complicated search condition, the elements are accessed more frequently.
That is, according to the hierarchical structure tracing means disclosed in JP-A 2001-034618 and 2000-057163 (Kokai), while the element data composing the hierarchical structures of the respective structured document data in the database are being traced, the structured document data having the element and structure specified by the search condition are searched for. For this reason, the search cannot be conducted at a high speed. Particularly, as the size of the structured document data is larger, the number of the structured document data to be searched for is larger or the query data (search condition) is more complicated, it is more difficult to heighten the speed of the search process. More concretely, such problems are as follows.
(1) In the case of complicated XQuery, the query includes a plurality of path patterns. When the plural path patterns are verified, traverse to one structured document occurs repeatedly. Particularly, in the case of treating the large size of the structured document data which cannot be on memory, disc I/O with respect to the same page occurs intermittently, and the performance is severely deteriorated.
(2) In the case of XPath which is the subset of XQuery, the performance is deteriorated at the time of high hit. That is, when most of the structured document aggregate is traversed, a lot of disc input/output (I/O) occurs.
As an idea of suppressing data scanning to the same structured document data, a technique of a structured document stream process is present. For example, the following references are included.
(Reference 1) Y. Diao, P. Fischer, and M. J. Franklin. YFilter: Efficient and Scalable Filtering of XML Documents. In The 18th International Conference of Data Engineering, San Jose, February 2002.
(Reference 2) I. Avila-Campillo, D. Raven, T. Green, A. Gupta, Y. Kadiyska, M. Onizuka, and D. Suciu. An XML Toolkit for Light-weight XML Stream Processing, 2002.
The process is for inquiring about Xpath or the like without storing not all the structured document data in a main storage. A system, which converts a plurality of path patterns appearing on plural XPaths into state transitions and processes them, is also proposed. Under present circumstances, however, the following problem arises.
(3) The performance is deteriorated notably on the XPath without high hit. Due to a back track base, an overhead for the CPU process is large. The inquiry process using indexes is difficult due to the property of the process.
As mentioned above, it is difficult to process a plurality of path patterns for the database which stores structured document data therein with minimum disc I/O and a small calculating amount.

Apparatus, program product and method for structured document management


The invention relates to a method of controlling the temperature of an injection mold, in particular for plastics and aluminium diecasting. The molten material being pressure-fed into the mold recess or the mold recesses of an injection mold by means of an extruder or the like in recurring cycles, cured therein, removed from the mold, and pressure-melted material being again supplied with the start of another cycle. A plurality of flow control valves are controlled by a sensor to provide an impulse or intermittent flow of the temperature control medium during each molding cycle at the same point in time as the previous cycle. The sensor compares a calculated temperature for a determined point in time of a molding cycle with the actual temperature of the molding cycle for that point in time and triggers the flow of temperature control medium for a set period of time to adjust the temperature of the molding cycle. This provides a more exact method of injection molding.

1. Field of the Invention
The invention relates to a method of controlling the temperature of an injection mold during each molding cycles of recurring molding cycles. A single molding cycle consists of pressure feeding molding material into the mold recess or the mold recesses of an injection mold, curing the material therein, and removing the molded material from the mold.
Applicant's method controls the temperature of the injection mold by comparing a present nominal temperature to an actual measured temperature, said actual temperature being measured by at least one temperature sensor. An amount of a cooling and heating medium is intermittently supplied to each molding cycle depending on the deviation of the measured actual temperature from the desired nominal temperature of the molding cycle. The comparison of the actual temperature and the nominal temperature is performed during each cycle at at least one point of time for each single molding cycle period. The method of controlling the temperature is suitable for use with plastic and aluminum die casting.
2. Background Art
A known method is shown in U.S. Pat. No. 4,420,446 or U.S. Pat. No. 4,354,812. In these known methods, the temperature of the injection mold is continuously sensed by means of a probe, and compared with a nominal value and, depending on whether the measured temperature exceeds or falls short of the desired nominal temperature, cooling fluid, in particular cooling water, is supplied through cooling channels or switched off. This method works without specifically taking into account the temperature distribution and the need of a cooling medium in the respective mold, these values varying extremely from case to case depending on the geometry and size of the mold. Consequently, optimal temperature distribution cannot be achieved with the known method. But optimal temperature control is needed to ensure a method which provides quality of the final product on the one hand, and achieves optimally short cycle times on the other hand. Cycle times must be adequately long enough to ensure sufficient curing of the molten material in the mold prior to ejection, but short enough to avoid excessive dwell times of the molded part of the mold. Temperature control must also be taken into account. Temperature control must ensure that even the most remote end of the mold recess, even for rather long mold channels, be reached by the still fluid injection-molding compound so that no cavities remain. On the other hand, the temperature control must be precise enough to avoid over heating the mold so as to require more of a cooling medium than necessary to be supplied for cooling and curing the molded part and thus increasing the amount of cooling time that has to pass.


White balance correction is performed on RGB color signals output from an image pickup device that includes a particular color filter array in which RGB color filters are arranged on respective lines and the ratios of the numbers of RGB color filters are different between the lines. For calculation of WB gains used for the white balance correction, not all the pixels of the image pickup device but prescribed lines are used to thinning-read. The WB gains are calculated based on color signals on the thinning-read prescribed lines. As the prescribed lines to be thinning-read, lines having a small degree of color mixture are selected under an imaging condition (a lens f-number and a zoom position) with a high degree of color mixture; lines having relatively even ratios of the numbers of RGB color filters are selected under an imaging condition having a low degree of color mixture.

1. Field of the Invention
The present invention relates to an imaging apparatus and an image processing method and, in particular, to technologies for speedily and accurately calculating a white balance gain.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. 2007-295300 (hereinafter referred to as PTL 1) discloses an imaging apparatus that calculates a white balance gain (WB gain) on the basis of an image thinned (extracted) from an image in the entire region of an image pickup device, actually takes an image in a part of the image pickup device through electronic zooming, and performs white balance correction with the calculated WB gain. Accordingly, a color temperature is detected from an image in a region having a higher probability that white exists than a region where an image is to be actually taken, thereby allowing a WB gain to be accurately calculated.
Japanese Patent Application Laid-Open No. 2003-116143 (hereinafter referred to as PTL 2) includes description where signals of pixels are thinning-read from a solid image pickup device, or signals of multiple pixels on lines with the same color in the vertical direction are added together and read, and a WB gain is calculated by detecting (an integration process of the level of each color) the read signals.
Incidentally, an image pickup device adopted in each of the imaging apparatuses described in the foregoing PTLs 1 and 2 has a color filter array that is a Bayer array (paragraph [0023] and FIG. 4 in PTL 1, and FIG. 3 in PTL 2).
In the Bayer array, green (G) pixels are arranged checkerwise and red (R) and blue (B) are line-sequentially arranged. Accordingly, there is a problem in that aliasing of a high frequency signal exceeding a reproduction band for each color and deviation in phase of each color cause coloring (color moire) at low frequencies.
In order to solve such a problem, a color image pickup device has been proposed that has a three-color random array satisfying an array limitation condition where any pixel concerned is adjacent to three colors including the color of the pixel concerned on any of four sides of the pixel concerned (Japanese Patent Application Laid-Open No. 2000-308080; PTL 3).
Japanese Patent Application Laid-Open No. 8-23542 (hereinafter referred to as PTL 4) proposes an imaging apparatus that includes G filters having a higher ratio than R filters and B filters to increase the color resolution in the horizontal direction and the vertical direction and reduce color moire in a luminance signal in comparison with the case where color filters with the same ratio are arranged in a lattice structure.


The invention relates to a method for selecting a way to perform a handover in a cellular radio system, and a cellular radio system employing code division multiple access. The system comprises in each cell at least one base station transmitting a pilot signal, and subscriber terminal equipments that may be connected to one or more base stations simultaneously, said terminal equipments comprising means for measuring pilot signals received by them, and comprising means for performing handovers of at least two types. For saving the capacity and the resources of the system, the terminal equipment of the system in accordance with the invention comprises means for selecting, on the basis of the pilot signals it has received, the handover technique which is used on the connection between the terminal equipment and the base station each time.

The invention relates to a method for selecting a way to perform a handover in a cellular radio system employing code division multiple access, and comprising in each cell at least one base station transmitting a pilot signal, and a number of subscriber terminal equipments that may be simultaneously connected to one or more base stations, said terminal equipments measuring pilot signals received, and being capable of performing handovers of at least two types.
The present invention is suited to be used in radio systems utilizing code division multiple access, and in particular in so-called WLL (Wireless Local Loop) systems. Code Division Multiple Access, CDMA is a multiple access method, which is based on the spread spectrum technique, and which has been applied recently in cellular communication systems, in addition to the prior FDMA and TDMA methods. CDMA has several advantages over the prior methods, such as spectral efficiency and the simplicity of frequency planning.
In CDMA, the narrow-band data signal of the user is multiplied to a relatively wide band by means of a spreading code having a remarkably broader band than the data signal. Bandwidths used in known test systems are e.g. 1.25 MHz, 10 MHz and 25 MHz. In connection with the multiplication, the data signal spreads onto the whole of the band used. All users transmit simultaneously by using the same frequency band. An individual spreading code is used on each connection between the base station and the mobile station, and the signals of different users may be distinguished from each other in the receivers on the basis of the spreading code of each user.
Adapted filters in the receivers are synchronized with the desired signal, which is identified on the basis of the spreading code. The data signal is returned in the receiver onto the original band by multiplying it by the same spreading code as in connection with the transmission. The signals which have been multiplied by some other spreading code neither correlate nor return to the narrow band in an ideal case. They thus appear as noise from the point of view of the desired signal. It is endeavoured to select the spreading codes of the system so that they are not mutually correlated, in other words, they are orthogonal. In practice, the spreading codes are not non-correlated, and the signals of other users complicate the detection of the desired signal by distorting the received signal. This interference caused by the users for each other is termed as multiple access interference.
In several CDMA systems in accordance with the prior art, a so-called pilot signal is used, which is transmitted by each base station and utilized in identification of base stations, power measurement, and for enabling coherent reception in a mobile station. The pilot signal is a data unmodulated spreading coded signal, and it is transmitted to the coverage area of the base station in the same way as the actual traffic channels. The coverage area of the pilot signal in fact determines the size of the cell of the base station, since the terminal equipments utilize it in call establishment.
The base stations continuously transmit the pilot signal, and the spreading codes used in the transmission of the pilot signal of different base stations differ from each other, so that a terminal equipment may identify the base stations on the basis of the pilot transmitted by them.
Systems in which a radio telephone network is used for replacing a conventional fixed telephone network are termed as WLL systems. In a WLL system, subscriber terminal equipments are fixed on the premises of the user, like a conventional telephone. In all data transmission methods utilizing a radio channel, interference occurs on the radio path, such as multipath fading of the signal, which is due to summing of such a signal in the receiver that has propagated several different ways. Since in a WLL system both the transmitter and the receiver are stationary, multipath fading is caused by the movements of the objects located in the surroundings. Thus, radio technically speaking, fading is very slow. A fading period usually varies from one second to a few seconds. Moreover, the fading depths may be so remarkable that they have an effect on the quality of the connection, in particular if the subscriber terminal equipment is located in the peripheral area of two cells.
A terminal equipment located in a peripheral area may meet with a situation in which a signal received from its own base station is fading just when a signal arriving from an adjacent base station is several decibels stronger than the desired signal. The signal-to-interference ratio of the signal received from its own base station, i.e. the quality of the connection may then decrease significantly. It is thus necessary to use a handover method of some kind between different base stations in the peripheral areas of a cell, which also takes multipath fading into account.
Known cellular radio systems, such as GSM, employ so-called hard handover, in which the terminal equipment communicates only with one base station at a time. If the quality of the connection weakens, a handover is performed to a new base station, the signal received from which is stronger.
CDMA cellular radio systems usually employ so-called soft handover. In soft handover, the terminal equipment may simultaneously communicate with more than one base stations during the handover. The base stations with which the terminal equipment may communicate are referred to as an active group. All the base stations with which the terminal equipment communicates transmit the same signal to the terminal equipment, which may select from said signals the strongest signal components, and advantageously combine them. The signal-to-interference ratio of the received signal may thus be maximized.
A parallel international application xe2x80x9cHandover method and a cellular radio systemxe2x80x9d PCT/FI95/00467 discloses a method in which the terminal equipment directly controls the transmission power of the base stations during a soft handover. By means of the method, it is possible to switch only the necessary base stations of the active group to transmit the signal to the terminal equipment.
Known methods, however, are attended by numerous drawbacks. If a hard handover is employed in a WLL system, taking multipath fading into account, it may result in a so-called ping-pong phenomenon, in which the connection is continuously switched between two base stations. This causes relatively much signalling on the radio path.
The drawback of soft handover in the WLL system is that extra interference power may unnecessarily be sent onto the radio path. Since the fading process of the signals sent from different base stations is not correlated, the signal received from one base station may be at its strongest simultaneously when the signal received from another base station is fading. If the fading is several decibels, the signal received from the latter base station is hardly of avail in the terminal equipment. Said signal, however, causes interference in the coverage area of said base station, and the capacity of the cell thus decreases. In conventional cellular radio systems, this problem is not relevant, as the fading processes are much faster. The disclosed situation may, however, last several seconds in the WLL system.
The method disclosed in a parallel international application xe2x80x9cHandover method and a cellular radio systemxe2x80x9d PCT/FI95/00467 is well suited for a WLL environment if the fading dynamics is relatively high, and the need for handover does not arise too frequently. It must be taken into account in the WLL system, however, that different directions of transmission are processes independent of each other. If the power control commands in the uplink direction are sent to the terminal equipment on the basis of the best connection in the uplink direction, it may be the case that the base station the downlink signal received from which is the best, does not hear the signal in the uplink direction.
Each of the above mentioned handover methods has its drawbacks that waste capacity and resources if the same method is used in the whole system.
The aim of the present invention is to implement a method in which the handover solution most appropriate for each situation is selected, said solution wasting as little capacity and resources as possible.
This is achieved with a method of the type set forth in the introduction, which is characterized in that the terminal equipment makes, on the basis of the pilot signals received by it, the decision on the handover technique used on the connection between the terminal equipment and the base station each time.
The invention further relates to a cellular radio system employing code division multiple access, and comprising in each cell at least one base station transmitting a pilot signal, and a number of subscriber terminal equipments that may be simultaneously connected to one or more base stations, said equipments comprising means for measuring the pilot signals received by them, and comprising means for performing handovers of at least two types. The cellular radio system of the invention is characterized in that the terminal equipment of the system comprises means for selecting on the basis of the pilot signals received by it the handover technique which is used on the connection between the terminal equipment and the base station each time.
By means of the method of the invention, transmission and processing of extra data connected with conventional methods may be avoided. On the basis of the measurements of the pilot signals, the terminal equipment may find out in advance which handover technique is the most advantageous each time. The terminal equipment measures pilot signals during a time period the length of which is essentially greater than the fading period of the radio channel. In WLL systems, the measuring time period may be as long as a half an hour. By means of the measurements during the connection, the way to perform the handover may also be changed during the connection. In a preferred embodiment of the invention, the terminal equipment calculates the power difference between the weakest and the strongest signal of the pilot signals received by it. In addition, the terminal equipment calculates on the basis of the pilot signals measured by it what is the estimated time distribution of handovers when only hard handovers are performed. On the basis of these parameters, the terminal equipment may conclude which handover technique is the most advantageous each time.

Method for selecting the way to perform a handover, and a cellular radio system