Disclosed, amongst other things, is: (i) a valve (220, 320, 420, 520, 620) for controlling air flow in an air pressure channel (354, 454) of a molded article holder (50, 150, 250, 350, 450); (ii) a molded article holder (350, 450) co-operable with the valve (220, 320, 420, 520, 620); and (iii) a post-mold holding device (315, 415) including the molded article holder (350, 450) and valve (220, 320, 420, 520, 620).

Some injection molded parts, for example plastic preforms of the variety that are for blow molding into beverage bottles, require extended cooling periods to solidify into substantially defect-free molded parts. To the extent that the cooling of the molded part can be effected outside of the injection mold by one or more post-mold holding devices then the productivity of the injection mold may be increased (i.e. lower cycle time). A variety of such post-mold holding devices, and related methods, are known and have proven effective at the optimization of the injection molding machine cycle time.
In a typical injection molding system, such as the system 10 depicted with reference to FIG. 1A, and as generally described in commonly assigned U.S. Pat. No. 6,171,541 (Inventor: NETER, Witold, et al.; Published: 9 Jan. 2001), just-molded, and hence partially cooled, molded articles 2 are ejected from the mold half 8, when the mold halves 8, 9 are spaced apart, and into molded article holders 50 (i.e. commonly known as a cooling tube, a take-off tube, or a cooling pipe, amongst others). The holders 50 are arranged on a molded article holding device 15 (i.e. commonly known as an end-of-arm-tool, carrier plate assembly, removal device, post-cooling apparatus, amongst others), the holding device 15 arranged to be cyclically positioned between an in-mold position, between the mold halves 8, 9, to receive the molded articles 2, and an out-board position, as depicted, to allow the mold halves 8, 9 to close and begin another molding cycle. Preferably, the molded articles 2 are held in the holders 50 until the molded articles 2 have cooled sufficiently that they may be ejected without risk of further deformation. While held in the holders 50, the cooling of the molded articles 2 may be assisted by the use of cooling/extraction pins 14 expelling a cooling fluid onto exposed portions of the molded articles 2. The cooling/extraction pins 14 are arranged on another molded article holding device 12 (i.e. commonly known as a COOLJET, a trademark of Husky Injection Molding Systems Ltd.), the holding device 12 arranged to be cyclically positioned between a cooling position, with the cooling/extraction pins 14 positioned adjacent the exposed portion of the molded articles 2, and an out-board position, as depicted. It is also known to use the cooling/extraction pins 14 to extract the molded articles 2 from the holders 50. The transfer of the molded articles between the holders 50 and the cooling/extraction pins 14 has been effected by various means. The steps involved in the typical transfer process include: (i) positioning the cooling/extraction pins 14 within a suitable region of the molded articles 2; (ii) connecting the cooling/extraction pins 14 to a negative pressure source, thereby creating a vacuum within the region of the molded articles 2; (iii) forcibly ejecting the molded articles 2 from the holders 50; once released from the holders 50, the molded articles 2 are captured by the cooling/extraction pins 14, under the applied vacuum, and the molded articles are extracted with the re-positioning of the holding device 12. The molded articles 2, extracted with the holding device 12, may then be re-handled and then ejected by the application of a positive fluid pressure through the cooling/extraction pins 14.
It is known to practice the step of forcibly ejecting the molded articles 2 from the holding device 15 by means of direct mechanical action, not shown. For example, commonly assigned U.S. Pat. No. 5,447,426 (Inventor: GESSNER, Dieter, et al.; Published: 5 Sep. 1995) describes a mechanically-actuated rail that bears against an outwardly extending portion of the molded articles, thereby forcing the molded articles from the holders. Such a means has proven to be a very reliable solution for ejecting the molded articles. However, not all molded articles have the requisite outwardly extending portion. In addition, such mechanical-based ejection systems do add significant weight to the holding device that requires larger driving motors to achieve the fast cycling speeds demanded by present productivity standards.
It has been known to configure the holder 50, as depicted with reference to FIG. 1B, to include a generally non-mechanical means for molded article ejection. In particular, the holder 50 includes a pressure channel 54 that is connectable to an air pressure source 18 via channel 18′, provided in a plate body 16. The pressure source 18 is configured to selectively provide overpressure or negative pressure through the pressure channel 54 to a cavity 52 defined along a tube 60 and tube insert 70. The pressure channel 54 includes a first portion, not shown, extending through the base of the tube, the first portion connecting a second portion, shown extending through a portion of the insert 70, with the pressure source 18′. The steps involved in the typical transfer process include: (i) configuring a suction air flow through the pressure channel 54 from the cavity 52 to the pressure source 18, the pressure source 18 configured as a negative pressure source, for effecting a transfer of the molded article 2 from the mold half 8 to the cavity 52; (ii) continuing the application of negative pressure through the pressure channel 54, to hold the molded article 2 in the cavity 52 of the holder 50, as the molded article 2 is cooled (by heat conduction through the tube 60 to a coolant circulating in the coolant channel 62 configured around the tube 60, and enclosed by a tube sleeve 64, the coolant channel 62 connectable to a coolant source 17, 17′ in the plate body 16); (iii) configuring the pressure source 18 to provide overpressure to the pressure channel 54, and thereby pressurize the cavity 52 and effect the ejection of the molded article 2 therefrom. Many factors affect the ejection of the molded article from the tube 2, including the geometry of the molded article 2 (e.g. a shallow draft angle on the outside of the molded article can cause the preform to stick in the tube). Suffice it to say, that not all of the molded articles 2 that are desired to be ejected simultaneously will release with common ease, and hence some molded articles may release earlier than others. Under such circumstances, when some subset of a total number of the molded articles are initially released, the cavity 52 of the corresponding holders 50 are at ambient pressure and hence the unchecked air flow from the pressure channel 54 is not being directed to the remaining holders 50 having molded articles 2 remaining therein. Accordingly, with the air flow losses associated with the venting holders 50, there may be insufficient air pressure remaining to dislodge the molded articles 2 that are more resistant to ejection in a timely manner, if at all.
FIG. 1B also shows that a fastener 72 is used to connect the holder 50 to the plate body 16, the holder configured to accommodate the fastener 72 along a passageway configured along a longitudinal axis of the holder 50. The foregoing arrangement while providing a readily serviceable connection, the technician merely needs to use a key through the pressure channel 54 to modify the connection, does have a significant drawback in that portions of the pressure channel 54, not shown, need to be off the longitudinal axis of the holder (namely the portion extending through the base of the tube 60). Accordingly, beyond the added complexity of manufacture, the foregoing arrangement does also suffer from a higher pressure drop between the pressure source 18 and the cavity 52.
Another example of a non-mechanical holder 150 is shown with reference to FIG. 2. The holder 150 is configured in much the same way as holder 50.
Wherever possible, similar features of the embodiments of the prior art and of the present invention have been given similar reference numbers and their descriptions have not been repeated.
The main difference between the two is that the holder 150 includes a checkable pressure channel 154, and an auxiliary pressure channel 136. The valve checkable pressure channel 154 includes a valve element 126 that is trapped between, at all times, a device portal 128 at the top of a portion of the pressure channel 154 that defines a valve chamber 124, and a plenum portal 130 configured at the base of the valve chamber 124. A valve seat 132 is configured adjacent the device portal 128 that cooperates with the valve element 126 for isolating the device and plenum portals 128, 130 when an overpressure is applied from the pressure source 118, 118′ to the pressure channel 154. The much narrower auxiliary pressure channel 136, relative to the pressure channel 154, is also connected to the pressure source 118, 118′, but without provision for a checkable valve. In addition, the insert 170 is configured to cooperate with the tube 160 and the fastener 72 such that it is movable along the longitudinal axis of the tube 160 to assist in supporting the molded article 2 as it is being ejected. The steps involved in the typical transfer process include: (i) configuring a suction air flow through both the pressure channel 154 (the valve element 126 resting in a configuration with respect to the plenum portal 130 such that the valve chamber maintains a fluid connection between the device and plenum portals 128, 130) and the auxiliary pressure channel 136, from the cavity 152 to the pressure source 118, the pressure source 118 configured as a negative pressure source, for affecting a transfer of the molded article 2 from the mold half 8 to the cavity 152; (ii) continuing the application of negative pressure through the pressure channels 154, 136, to hold the molded article 2 in the cavity 152 of the holder 150, as the molded article 2 is cooled; (iii) configuring the pressure source 118 to provide overpressure to the pressure channels 154, 136, the valve element 126 moving to cooperate with the valve seat 132, isolating the device portal 128 from the pressure source 118, as soon as air begins to flow into the cavity 152, the air flow through the auxiliary pressure channel 136 continuing unchecked (the auxiliary channel includes an outlet nozzle 138, which may assist in moving the insert 170 forward during ejection). The foregoing arrangement provides for reduced air pressure losses from empty holders 150, relative to the holder 50, the losses mitigated by the pressure losses through the relatively narrow auxiliary channel. Nonetheless, the auxiliary channel 136 and portions 154A and 154B of the pressure channel 154 are off-axis relative to a common connecting portion 154C of the pressure channel 154, with associated pressure losses which can affect the efficacy of the transfer from the mold 8 into the holder 150. Perhaps of more significance, is the pressure losses associated with the circuitous route in which the air must flow around the valve element 126 when effecting a suction air flow through the valve chamber 124. In particular, the device and plenum portals 128, 130 are arranged on opposite sides of the valve element 126 at all times thereby requiring the air to flow past the rather narrow gaps between the valve element and the valve chamber 124 and with associated pressure losses.
European Patent 1 123 189 B1 (Inventor: WEINMANN, Robert, et al.; Published: 29 Jan. 2003) provides yet another example of a non-mechanical variety of molded article holder that includes a pressure-biased valve check pin for controlling air flow between a cavity, defined in the holder, with a pressure source.

Valve for controlling air flow in a molded article holder


An undermount drawer slide mounting clip releasably attaches a drawer to a drawer rail assembly mounted in a cabinet carcass. The apparatus is capable of effecting positional adjustments of the drawer in three directions without removing the drawer from the cabinet carcass. The apparatus is comprised of a body slidingly engaged with a bonnet. A trigger pivotally connected between the body and the bonnet. A spring loaded catch slidable within the bonnet and acted on by the trigger to releasably attach the apparatus to a drawer rail assembly. A threaded spindle rotates within the base and adjusts the horizontal position of the drawer. A ramp adjustably connected to the base adjusts the vertical position of the drawer by rotation of a threaded barrel. A plunger extends from a housing connected to the body to adjacent the drawer rail assembly and adjusts the depth of the drawer.

Drawer slide assemblies typically include telescoping slides mounted to the interior of the cabinet carcass and the drawer. Drawer slides are typically mounted on the bottom or the sides of the drawer and cooperate to allow the drawer to be opened or closed. Undermount drawer slides have several advantages over side mounted drawer slides. For example, increased weight bearing capacity and drawer width. Another advantage of undermount drawer slides is that they are hidden from normal view when the drawer is open, improving the aesthetic appeal of the drawer and the cabinet.
Proper alignment of the drawer face with the cabinet face is also important to appearance of the drawer and cabinet. Proper adjustment of the drawer face in three directions, "horizontal," "vertical," and "depth."
Unwanted changes in drawer face adjustments over time generally occurs due to use of the drawer. These changes represent a problem in the art because of the resulting poor appearance of the drawer over time. Eliminating such unwanted changes is desirable.
The prior art offers many partial solutions to the necessity of adjusting a drawer face relative to a cabinet carcass. However, none of these solutions provide a way to secure adjustments over time.
For example, U.S. Pat. No. 6,913,334 to Weichelt discloses a device for establishing an adjustable connection between a drawer and a furniture guide rail. The device comprises a base part adapted for connection to the drawer and a detent recess adapted for connection to the guide rail. The tolerance between the drawer and the guide rail may be manually adjusted in two directions. A furniture guide rail includes a suitable detent for engagement with the detent recess. No provision is made to prevent the adjustments from changing during use of the slides.
U.S. Pat. No. 8,424,984 to Ritter discloses an apparatus for releasably coupling a drawer to a drawer pull-out guide. The apparatus comprises a holding part which interacts with a mating part of the guide rail. The holding part is flexible to compensate for longitudinal play of the drawer in relation to the rail. The apparatus allows for depth and horizontal adjustment, but makes no provision for preventing movement of the adjustments while the drawer is in use.
U.S. Publication No. 2012/0292465 to Holzer, et al. discloses a coupling device for a drawer. The device includes a fixing portion mounted to the drawer and a coupling portion for attachment to a guide rail. The device is capable of providing adjustments in a vertical direction and a horizontal direction.
U.S. Pat. No. 9,101,213 to McGregor, et al. discloses a device that provides for adjustment in three directions, horizontal, vertical, and depth. However, the device does not provide mechanisms to retain adjustments over time. The device also does not provide for incremental vertical adjustments.
A simple, cost effective solution for attaching a drawer to a drawer slide assembly that provides directional adjustment with relative permanence is needed. Further, there is also a need for an undermount clip that may be adjusted without use of tools.

This patent is subject to a terminal disclaimer.

Undermount drawer slide position adjustment apparatus and method of use


A control method for operating aqueous Haematococcus spp., such as H. pluvialis, microorganism growth processes is disclosed which can maintain viable growth conditions of this microorganism which have heretofore not been easily reproduced in commercially valuable quantities. The primary control parameters are the degree of turbulence in the aqueous growth medium and the scale of the apparatus relative to the scale of the turbulent eddies in vessels which are partially filled with the aqueous medium directly affect conditions which are required for optimum growth: light exposure, nutrient supply, sedimentation rate, bulk temperature, gas exchange rate and cell integrity. These control elements can be cast in terms of the Reynolds number (N.sub.re), pH, temperature, amount of impinging light, and NO.sub.2 concentration, depending upon the operative chlorophyll growth stages of Haematococcus spp. and its photoadaptive stages of producing astaxanthin.

1. Field of the Invention
The invention herein relates to the extraction of natural products from microorganisms, especially algae. More particularly it relates to control of large size aqueous photosynthetic bioreactor systems to obtain such products from the microbial genus Haematococcus, which has heretofore only been cultured in laboratory environments in small containers.
2. Description of the Prior Art
In view of environmental constraints, economics, and various other factors, astaxanthin, which is currently produced by chemical synthesis from petroleum- or coal-derived raw materials is coming into disfavor or is facing restrictions or outright bans from the marketplace. For instance, aniline-based sources of astaxanthin dyes are or will soon be phased out by government regulation in Europe, and similar restrictions or bans are likely to arise soon in other areas of the world, including the United States. Consequently there is a major research and development effort going on worldwide to find natural sources for astaxanthin.
It has been known that astaxanthin can be obtained from certain species of microorganisms, in particular those of the unicellular alga genus Haematococcus. Upon exposure to light, this alga genus produces astaxanthin by photosynthesis. If Haematococcus species, such as H. pluvialis, could be cultivated on a mass production basis, a valuable and economic natural source for this dye would be available.
The obvious utility of mass production of photosynthetic microorganisms resides in the process of photosynthesis itself. Given the appropriate supply of light, water, carbon dioxide (CO.sub.2), and control of temperature, pH and the aqueous environment motions (e.g., turbulence), photosynthetic microorganisms can utilize sources of essential nutrients such as nitrogen (N) and phosphorous (P) to convert solar energy into chemical energy. Thus, the process of growing or culturing photosynthetic microorganisms involves the introduction of nutritionally complete medium to a contained volume of culture, maintenance of optimal growth conditions in that volume, and subsequent harvest or removal of the microbial cells from the spent medium. All culture programs must devise methods to accomplish each of these phases of the production process efficiently.
Of these requirements the most difficult to achieve is usually the step of maintaining optimum growth which equates to economically feasible production. Haematococcus species from which astaxanthin is derived are very sensitive, by an order of magnitude, to small changes in growth environment. It is common, for instance, for a researcher to develop a protocol for maintaining H. pluvialis in the laboratory in a small volume in a laboratory container, only to have the system fail dramatically in large size volume required for economic field production, where control of system parameters is much more difficult and more variables can be encountered.
For example, one photosynthetic growth mechanism, known as the "flashing light effect," i.e., the ability of some photosynthetic cells to effectively use energy from an intermittent light source see, e.g. Emerson, et al., J. Gen Physiol., 15(4):391-420 (1932)!, has not been effectively utilized in a mass culture system, because it depends on the turbulent flow regime in the growth media that exposes cells intermittently to a light source. Too much or too little exposure results in decreased production of microorganisms. A method or apparatus has been developed by Applicants which maximizes the flashing light effect by use of controlled turbulent flow regime such that this effect could be utilized in a mass culture system, thus enhancing the efficiency and productivity of that system for Haematococcus spp.
It has been known that one must avoid excessive shear in the fluid on the scale of the microorganism, in order to prevent destruction of the microbial mass. For instance, Thomas et al., J. App. Phycology, 2:71-77 (1990) reported that in small gap rotating cylinders at Reynolds Numbers above 116 (and up to 3500) cell growth rate became negative, i.e., that the microbial mass was dying, not growing. Thus, the dimensions or mechanical configuration of the apparatus must also be controlled in order to alleviate the deleterious effects of turbulence on cell integrity.
The concept of culturing microorganisms in open or closed systems and harvesting a product from the microorganisms is not new. There are numerous systems used throughout the world in which algae or phytoplankton are grown and harvested, either for direct usage (as for animal food) or for indirect usage (as sources of chemicals such as carotenes). However, almost all such systems operate on only a very few species of microorganisms; i.e., those which have been found to be tolerant to the widest range of growth conditions and which produce relatively simple products. This in turn has limited the industry to production of a very small number of products compared with what has been extracted in laboratory scale, experimental cultures. Efforts that have been made to culture Haematococcus for production of astaxanthin have been failures because laboratory cultures have not been made to survive or grow economically in large scale volumes. Furthermore, Haematococcus spp. which will tolerate the fairly crudely controlled processes of the past (either open or closed systems) have not been capable of yielding astaxanthin, either directly or indirectly, in economical quantities. Haematococcus has not proved amenable to culture in the current systems, since such systems cannot be controlled in a sufficiently precise manner to maintain adequate health and growth of Haematococcus which may have been grown on a small scale in a laboratory. Laboratory scale apparatuses generally do not contain turbulent flows, while commercial production scale systems do. Heretofore, the necessity of control of turbulence has not been recognized as a crucial factor in mass culture apparatus, as the Applicants have found to be necessary for the health of Haematococcus microorganisms.
Numerous operating conditions or factors are critical in commercially viable production of astaxanthin from condition-sensitive Haematococcus spp. Consequently, a system in which precise control of these operating conditions is accomplished will permit not only large scale culturing of Haematococcus spp., which cannot now be grown by existing commercial technology, but also the mass production of natural astaxanthin which is not currently available on an economic basis in the marketplace.

Method of control of Haematococcus spp, growth process


A communications system includes at least one low earth orbit first satellite (10), at least one second satellite (11) in other than a low earth orbit, and a ground segment (12) that includes a plurality of user transceivers (78, 80, 82, 84) and at least one gateway (76) coupled to a publicly-accessible terrestrial communications system, such as a PSTN and/or a fiber optic network. The first satellite includes a first transceiver for communication with the at least one gateway, a second transceiver for communication with at least one user transceiver, and a third transceiver for communication with the at least one second satellite. The first, second and third transceivers are switchably coupled together on-board the first satellite by on-board processors and a switching matrix for relaying a user communication between the at least one gateway and the at least one user transceiver via the at least one second satellite. The plurality of user transceivers can include a plurality of data processors which are interconnected into a network through the at least one first satellite. This network can be considered as a virtual network, and can have a mesh, star, or other topology. The user transceivers can be adapted to transmit and receive direct sequence, code division/multiple access communications. Transmission of signals to and from the user transceivers is accomplished by spreading a digital data stream (e.g., voice, data, image, video) with assigned spreading codes.

Satellite delivered individual services are emerging as a new global enterprise. These systems utilize or are proposed to utilize many individual circuits routed through one satellite or a constellation of many satellites to effect communications. One value of the satellite system is that it provides ubiquitous coverage of large areas of the earth without the construction of ground-based infrastructure. Since the recent availability of portions of the frequency spectrum for these services, several proposals have been advanced by a number of organizations. One proposal would use Time Division Multiple Access (TDMA), while several others would employ Code Division Multiple access (CDMA). A feature of the CDMA systems is an ability to share the available frequencies by co-frequency operation, while experiencing only a percentage decrease in the capacity of each system.
Furthermore, Low Earth Orbiting Satellite (LEOS) systems, also referred to as Non-GSO (geosynchronous orbit) satellite systems, offer a new dimension in communications. For example, the LEOS systems can provide diversity, as described in U.S. Pat. No. 5,233,626, issued Aug. 3, 1993, entitled "Repeater Diversity Spread Spectrum Communication System", to Stephen A. Ames. Another capability provided by the LEOS systems is an ability to interconnect users to a fixed point, typically referred to as a Public Switched Telephone Network (PSTN).
High capacity, fiber optic-based communications is currently being deployed world-wide, and in particular in the United States, to directly connect to subscribers in their homes. In addition to providing conventional voice communication capability, the fiber optic-based networks can also provide video and high speed data capabilities. The proliferation of networked personal computers having multimedia capabilities can take advantage of the increased speed and capacity provided by the fiber optic based networks. However, the significant costs involved in providing fiber optic lines is not economical in every locale, and it can be expected that large non-urban areas will not be in a position to benefit from the advantages provided by fiber optic networks within a reasonable period of time.

Interactive fixed and mobile satellite network


A medical gas utility stand for connection to at least one remote medical gas source, each medical gas source detachably connectable to a gas conduit line so that the gas conduit line is in fluid communication with one medical gas source. The gas utility stand includes a base connected to a substantially upright support member. The gas utility stand also includes a gas connection member having at least one gas conduit defining a gas passage extending between an input end and an output end, the gas connection member fixedly connected to the support member adjacent its top end. Additionally, the gas utility stand has at least one pair of identical gas fittings, each gas fitting defining a bore extending between an attachment end and a securing end, the securing ends of one pair of identical gas fittings detachably secured to the opposing input end and output end of one gas conduit so that the bores of the pair of identical gas fittings are in communication with the gas passage of the gas conduit. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Applicant""s present invention is directed to a medical gas utility stand for connection to at least one remote medical gas source. The medical gas utility stand of the present invention allows for the remote gas sources, which are typically located the walls of hospital room, to be effectively organized and to be brought into proximity of the medical apparatuses that require the use of the various gases. The gas utility stand includes a base, a support member, a gas connection member and at least one pair of identical gas fittings. The base is in operative contact with a support surface such as a floor or the ground and is connected to the bottom end of the support member.
The gas connection member has at least one gas conduit having an input end and an opposing output end. The gas conduit defines a gas passage extending between the input end and the output end. The gas connection member is preferably fixedly connected to the support member near the top end of the support member. Each gas fitting has an attachment end and an opposing securing end and defines a bore extending between the attachment end and the securing end. The securing ends of one pair of identical gas fittings are detachably secured to the opposing input end and output end of one gas conduit so that the bores of the pair of identical gas fittings are in communication with the gas passage of the gas conduit.
Because different types of identical gas fittings can be secured to the input and output end of each gas conduit, the gas utility stand of the present invention advantagously allows a user to selectively choose any desired combination of medical gases desired by simply selecting the appropriate pair of identical gas fittings for each specific gas conduit. As one skilled in the art will appreciate, each gas fitting has a unique shape based upon a specific type of medical gas. Therefore, because of each gas fitting""s unique shape, only medical accessories, medical equipment and/or gas conduit lines that are designed to utilize the specific medical gas may be detachably secured to the attachment end of a given gas fitting.
The gas utility stand may also have at least one gas conduit line. Each gas conduit line has a first end and a second end. Additionally, each gas line has a pair of gas connectors. One gas connector is fixedly attached to the first end and the other gas connector is fixedly attached to the second end of the gas conduit line. As one skilled in the art will appreciate, each gas connector has a shape that is complementary to the attachment end of one type of gas fitting. In operation, the gas connector at the first end of the gas conduit line is detachably connected to attachment end of one gas fitting that is secured within the input end of one gas conduit. Further, the gas connector at the second end of the gas conduit line is detachably connected to one medical gas source. Thus, the gas conduit line is in fluid communication with one medical gas source and, resultantly, the attachment end of the gas fitting that is detachably secured within the opposing output end of the gas conduit is in fluid communication with the one medical gas source. Because of the requirement that the shapes of the attachment end of the gas fitting and the gas connector be complementary for operable connection of the gas connector to the attachment end of the gas fitting, only the desired gas conduit line having the appropriate gas connectors can be detachable secured to a specific gas fitting. This ensures that only the desired medical gas from the medical gas source is supplied to the gas conduit.
In a second embodiment of the invention, the gas utility stand may also have a mounting plate that is detachably attached to the support member intermediate the base and the gas connection member. The mounting plate has a plurality of slide brackets for the detachable attachment of medical accessories.
In a third embodiment of the present invention, the gas utility stand may also include a hose bracket plate that is detachably attached to the support member intermediate the base and the gas connection member. The bracket plate has at least one pair of opposing toggle hangers that are connected to the front surface of the bracket plate. Each pair of opposing toggle switches define a pair of opposed slots so that a coil of the gas conduit line can be removably secured within the defined slots.
In a fourth embodiment of the present invention, the gas utility stand may also include both a mounting plate and a hose bracket plate as previously described. It is preferred that the mounting plate be detachably connected to the support member proximate the base and the bracket plate be detachably mounted to the support member intermediate the mounting plate and the gas connection member.


A storage router (56) and storage network (50) provide virtual local storage on remote SCSI storage devices (60, 62, 64) to Fiber Channel devices. A plurality of Fiber Channel devices, such as workstations (58), are connected to a Fiber Channel transport medium (52), and a plurality of SCSI storage devices (60, 62, 64) are connected to a SCSI bus transport medium (54). The storage router (56) interfaces between the Fiber Channel transport medium (52) and the SCSI bus transport medium (54). The storage router (56) maps between the workstations (58) and the SCSI storage devices (60, 62, 64) and implements access controls for storage space on the SCSI storage devices (60, 62, 64). The storage router (56) then allows access from the workstations (58) to the SCSI storage devices (60, 62, 64) using native low level, block protocol in accordance with the mapping and the access controls.

Typical storage transport mediums provide for a relatively small number of devices to be attached over relatively short distances. One such transport medium is a Small Computer System Interface (SCSI) protocol, the structure and operation of which is generally well known as is described, for example, in the SCSI-1, SCSI-2 and SCSI-3 specifications. High speed serial interconnects provide enhanced capability to attach a large number of high speed devices to a common storage transport medium over large distances. One such serial interconnect is Fibre Channel, the structure and operation of which is described, for example, in Fibre Channel Physical and Signaling Interface (FC-PH), ANSI X3.230 Fibre Channel Arbitrated Loop (FC-AL), and ANSI X3.272 Fibre Channel Private Loop Direct Attach (FC-PLDA).
Conventional computing devices, such as computer workstations, generally access storage locally or through network interconnects. Local storage typically consists of a disk drive, tape drive, CD-ROM drive or other storage device contained within, or locally connected to the workstation. The workstation provides a file system structure, that includes security controls, with access to the local storage device through native low level, block protocols. These protocols map directly to the mechanisms used by the storage device and consist of data requests without security controls. Network interconnects typically provide access for a large number of computing devices to data storage on a remote network server. The remote network server provides file system structure, access control, and other miscellaneous capabilities that include the network interface. Access to data through the network server is through network protocols that the server must translate into low level requests to the storage device. A workstation with access to the server storage must translate its file system protocols into network protocols that are used to communicate with the server. Consequently, from the perspective of a workstation, or other computing device, seeking to access such server data, the access is much slower than access to data on a local storage device.

Storage router and method for providing virtual local storage


To provide a Colpitts oscillation circuit formed with a quartz resonator and a transistor amplifier circuit, which can secure sufficient negative resistance, obtain stable oscillation, negate the need for an amplitude control circuit, and realize stabilization against temperature variations. In order to solve the problem, a structure in which the impedance of a tuning circuit provided in a collector of the transistor exhibits inductivity at the oscillation frequency is provided. The impedance ratio at the oscillation frequency of a capacitor C2 connected between a base and an emitter to a capacitor C3 connected between the emitter and a ground, of the transistor is set at 3 to 1 or more. Furthermore, the impedance of capacity C2 connected between the base and the emitter at the oscillation frequency is set at 300 Ω or more. A bias resistance R1 connected between the collector and the base of the transistor is set at 3 kΩ or less. A temperature compensation diode D1 is inserted in series between the base and the ground (GND) between the transistor.

1. Field of the Invention
The present invention relates to a sensing device which is provided with an adsorption layer for adsorbing a sensing target on an electrode surface of a piezoelectric resonator such as a quartz resonator, and detects and measures the sensing target based on variation in natural frequency of the quartz resonator caused by adsorption of the sensing target to the adsorption layer, especially to a Colpitts oscillation circuit formed with a quartz resonator and a transistor amplifier circuit.
2. Description of the Related Art
This kind of the sensing devices is commercially practical as a device which, for instance, combines a substance to be measured with the antibody to make an immune reaction with the substance to be measured, utilizing an antigen-antibody reaction as an immune reaction, and detects and measures the substance to be measured based on the degree of the reaction.
FIG. 10 shows a basic structure of a sensing device. An piezoelectric resonator, for instance, a quartz resonator 100 is structured by forming electrodes 102 and 103 on both surfaces of a quartz substrate 101, and is fixed in a receptacle 104. The electrodes 102 and 103 are connected to an oscillation circuit 107 through lead wires 105 and 106, and the oscillation circuit 107 oscillates at the natural frequency of the quartz resonator 100. The oscillation output of the oscillation circuit 107 is detected by a frequency counter 108 as a frequency signal, and the frequency of the frequency signal is displayed on a display 109. The antibody is applied to the surface of the electrode 102 which is one of the electrodes of the quartz resonator. The amount of adsorption of the substance to be measured on the antibody is measured as change in oscillation frequency of the oscillation circuit 107 by bringing the electrode 102 into contact with a solution containing the substance to be measured (refer to, for instance, Patent Document 1).
Here, the oscillation circuit 107 using the quartz resonator is structured as a Colpitts oscillation circuit or a Hartley oscillation circuit which can generally perform oscillation operation with a quartz resonator and an amplifier. As the amplifier, an analogue amplifier provided with a feedback circuit between an output and an input of an inverting logic element, or a transistor amplifier circuit with a transistor and a capacitor or a resistor is used.
[Patent Document 1] Japanese Patent Application Laid-open No. 2001-83154


This disclosure involves improved route recommendation in map service. A computer-implemented method comprises identifying at least one intermediate point for traveling from an origin to a destination based on a user input. The method further comprises determining one or more first recommended routes from the origin to the destination via the at least one intermediate point. The method further comprises determining one or more second recommended routes from the origin to the destination without considering the at least one intermediate point. The method further comprises in response to at least one of the first recommended routes being better than the second recommended routes, storing the at least one intermediate point associated with the origin and the destination.

The present invention relates to information processing, and more specifically, to map service.
Today, map service on computing devices, e.g., cell phones, GPS navigation devices and portable computers, is widely used all over the world, and route recommendation is one of the most popular functions of the map service. Many searching algorithms, such as Dijkstra's algorithm, Bellman-Ford algorithm, A* search algorithm, Floyd-Warshall algorithm, Johnson's algorithm and Viterbi algorithm, have been developed to facilitate searching of the optimal route between an origin and a destination. Due to the requirement for quick response and high concurrency for route recommendation in the map service, heuristic algorithms are usually used for route recommendation. However, in most cases, heuristic algorithms cannot guarantee a theoretically optimal solution.

International Business Machines Corporation


The invention relates to a device to aid the orientation of blind and partially sighted people. The device comprises a long cane and an additional device comprising a laser measuring system. By transmitting and receiving laser beams the laser measuring system detects objects in a planar detection area of a detection plane containing the long cane. Indicating means indicates the presence and the absence of objects in this planar detection area by a first and by a second information, respectively, for example by the presence of a determined signal and by the absence of a determined signal. This allows to detect objects above the long cane.

This invention relates to a device to aid the orientation of blind and partially sighted people.
Blind or partially sighted people usually use a cane (so-called mobility cane or long cane) for orientation, with which objects in a distance up to 1.2 m can be detected. The orientation with such a long cane has several disadvantages. For example, objects cannot be detected if they are not located near the ground and within a distance of about 1.2 m. The head and the breast area of the blind person cannot be protected. Objects in this height are often recognised to late which often result in hurting the blind person.
A number of devices for blind or partially sighted people is known which use contactless distance measurement systems to overcome the disadvantages of the long cane. Different versions of such a contactless distance measurement system are known. These devices comprise a transmitter which sends out a measurement beam and if the beam is reflected by an object a receiver detects the reflected beam. The distance between the device and the object is determined either by time of flight measurement, phase modulation measurement or by triangulation measurement. The measurement beam can be electro-magnetic (IR-radiation or laser beam) or sonic. The determined distance will be converted into a distance-dependent correcting variable which will be supplied to an indicator that displays the distance in a way that is adapted to the needs of the blind and partially sighted persons. Such indicators use either acoustic or tactile signals.
Furthermore, long cane are known, which are provided with an additional device comprising a contactless measuring system by means of which space ranges are detected, which cannot be detected by the long cane itself. The beam lobe of the measuring system is directed in the walking direction and considerably exceeds the range of the long cane. Due to the extended beam lobe (particularly when using ultrasonic devices) such additional devices detects a large space area. When an object is detected in this space area, a warning signal is supplied to the blind person.
It has been found that known contactless measuring devices, regardless whether they arc used in combination with a long cane or not, have disadvantages which make them very uncomfortable in use. The known devices generate warning signals or distance signals for indicating objects which are not located in the range relevant for the blind person. The user receives a large amount of signals which are very hard to interpret and which disturb the orientation of the blind person.
The object of the present invention is hence to provide a device to aid the orientation of blind and partially sighted people, by means of which device the head and breast area of the blind person is protectable without supplying unnecessary signals.
According to the invention, this object is achieved by a device comprising a cane, and further comprising measuring means comprising laser source means generating laser beams and laser light detecting means responding to laser light from said laser source means, said laser source means and said laser light detecting means being arranged to define a planar detection area in a detection plane comprising said cane, and indicating means for indicating the presence and the absence of an object in said planar detection area by a first and a second information, respectively.
The invention is based on the realization that the use of a device to aid the orientation of blind people is acceptable to the blind person only if the information signals concerning an obstacle can be interpreted without further considerations. Most of the blind persons are used to the long cane and even trained in use of such a long cane.
The device according to the present invention does not replace the long cane but is a combination of a long cane and an additional device comprising measuring means and indicating means. The operation of the additional device is such that it xe2x80x9csimulatesxe2x80x9d the use of the long cane. This is effected in that the additional device only detects a determined area (xe2x80x9cplanar detection areaxe2x80x9d) in a determined plane (xe2x80x9cdetection planexe2x80x9d). This plane is selected such that it comprises the long cane When the blind person moves the long cane in usual manner laterally to the left and to the right in order to scan the ground with the tip of the long cane, then the space above the long cane is detected by the additional device in such a manner that only a two-dimensional area above and in the prolongation of the long cane is detected. The additional device indicates the presence of an object in this planar area by providing a first information as well as the absence of an object in this planar detection area by providing a second information. The first information can, for example, be constituted by the presence of a particular (acoustic or tactile) signal and the second information can be constituted by the absence of a particular (acoustic or tactile) signal, or vice versa. The effect of this scanning is similar to the effect of scanning this space by the long cane itself, that means if the blind person could move the long cane to the left and to the right and simultaneously move it up and down. (Such a simultaneous movement of the long cane is, of course, not possible.) By this functional similarity with the function of the long cane itself, the device according to the invention does not require any training.
The principle of the measuring means used in the present invention for detecting objects in the planar detection area could be any known contactless operating principle used for measuring distances, for example the principle of time of flight measurement, the principle of triangulation measurement or the principle of phase modulation measurement. Such principle are known per se and therefore not described in detail herein.
In a preferred embodiment of the invention the measuring means operate according the principle of time of flight measurement of laser pulses. In this embodiment the laser source means are formed by laser pulse generating means for generating laser pulses. The laser light detecting means are formed by photodetector means responding to the laser pulses generated be the laser pulse generating means and reflected by an object in the planar detection area. Furthermore, signal processing means are provided. These signal processing means determine the duration between generating or sending a laser pulse by the laser pulse generating means and detecting this laser pulse by the photodetector means in relation to a predetermined duration. The laser pulse generating means can comprise one single laser source or several laser sources as well as the photodetector means can comprise one single photodetector or several photodetectors.
One possibility to arrange the measuring means to define a planar detection area exclusively in the selected detection plane can be achieved by generating several laser beams which all are located side by side in this detection plane. The number of laser beams and the closeness will then depend on the desired accuracy of detection.
A further possibility to arrange the measuring means to define a planar detection area exclusively in the selected detection plane can be achieved in that the generated laser beams are deflected by beam deflection means such that the beams are deflected in the planar detection area. Such beam deflection means can be means which either changes the direction of a beam or which deflects the beam such that the divergence of the beam is varied, for example increased in one direction or decreased in another direction to fan out the hewn. These beam deflection means can comprise, for example, an oscillating mirror which periodically deflects laser beams, for example, from one single laser source such that the two-dimensional detection area is scanned by the deflected laser beam. The beam deflection means can also comprise other beam deflection components as, for example, a prism. As mentioned above, the beam deflection means can be Laser beam divergence influencing means by which the divergence of the laser beams generated by said laser source means is increased two-dimensionally, that means in the detection plane, or decreased in a plane perpendicular to the detection plane. Such laser beam influencing means are known and can, for example, comprise a lens system having cylindrical lenses. Such beam divergence influencing means effect the laser beam to fan out in one plane and to cover an area, the extension of which depending on the extension of the angle of divergence of the beam. By using such beam divergence influencing means the planar detection area can be covered by one single laser beam having increased divergence, instead of several individual laser beams. Furthermore, this ensures that the entire planar detection area is simultaneously covered by laser radiation.
Advantageously, the device comprises limiting means for restricting the planar detection area such that the planar detection area is defined by determined limits. These limit can be defined as a function of the length of the long cane, of the extension of the long cane and of the height of the blind person using the device. Limit varying means can be provided for varying these limits of the planar detection area. These limit varying means can be used in order to individually adapt the desired planar detection area to individually different heights or individually different desires concerning the extension of the planar detection area
At least one of the limits of the planar detection area can be determined by fixed or variable beam limiting means for limiting the laser beams. Such beam limiting means can, for example, be beam divergence limiting means such as filters, stop means, diaphragms or lenses, for example a cylindrical lens. The limits can be varied, for example, by replacing the lens system by another lens system having other properties with respect to the achieved beam divergence.
Furthermore, at least one of the limits of the planar detection area can be determined by time range means for defining a fixed or variable time range for detecting the laser pulses by the photodetector means. The time range can be varied by varying the time constant of a RC-network using, for example, a potentiometer. This time range can be triggered by the laser pulse generated by the laser pulse generating means. If the duration between generating the laser pulse and detecting the laser pulse is shorter than this time constant, then the object reflecting the laser pulse is located within this limit of the planar detection area. If, however, the duration between generating die laser pulse and detecting the laser pulse is longer than this time constant, then the object reflecting the laser pulse is located beyond this limit of the planar detection area.
If the long cane and the additional device is rotated or inclined, then the detection plane of the planar detection area is inclined relative to the vertical plane. This can be done on purpose in order to scan objects located laterally from the long cane. However, this tilting can be done by mistake and the blind person still thinks that the detection plane of planar detection area is vertical. In order to avoid this, inclination sensor means can be provided for determining the inclination of the detection plane of the planar detection area relative to a vertical plane. These inclination sensor means can be arranged to define a threshold angle and to generate a sensor signal when the detection plane of the planar detection area is inclined by more than this threshold angle relative to a vertical plane. This signal can be a warning signal generated by inclination indication means in the form, for example, of a tone generator indicating to the blind person that the detection plane is not aligned with the vertical plane. The amount of the inclination triggering the warning signal is determined by the threshold angle. It could be useful to define a time period between exceeding the threshold angle and generating the warning signal such that, for example, no warning signal is generated when the detection plane is inclined for only a short time in order to scan objects located laterally from the long cane. The signal generated by the inclination sensor means can also be a control signal for controlling the additional device to rotate the detection plane into the vertical plane or for turning off the laser source means.
However, the inclination indicating means can also be represented by a perceptible feature provided on the long cane or on the additional device. This perceptible feature can be an asymmetric handle of the long cane. In this case, the blind person knows in which direction the detection plane is pointing just by holding this handle in his hand.
The measuring means, the indicating and/or the inclination sensor means can be provided on the long cane in different manner. For example, they can be accommodated in a common housing or in individual housings. This or these housings can be integral with the long cane, for example be an integral part of the handle. However, the hosing or housings can also be attachable to the long cane by means of attachment means (for example screws or the like). In this way it is possible to provide an already existing long cane with the additional device defined herein.
Further objects and features of the invention will be apparent to a person skilled in the art from the following specification of a preferred embodiment when read in conjunction with the appended claims.

Device to aid the orientation of blind and partially sighted people


A method for providing panoramic videos and images to a user using a server-client architecture while minimizing the wait time necessary before still images are available for viewing or videos begin playing. A series of location-referenced panoramic images are separated into one-dimensional tracks. Intuitive user controls are provided which allow the user to start and stop video playback, step through the panoramas in a track one at a time, and change the viewing orientation within the panorama. A video will start playing as soon as the video files for the preferred projected cube faces have been downloaded. This delay is reduced by storing the videos as keyframe distance files for opposing directions for each cube face and further reduced by encoding videos with different starting points so that they are staggered by a portion of the keyframe distance.

1. Field of the Invention
The invention relates to providing panoramic video, and more particularly to providing it between a server and a user over a network.
2. Description of the Related Art
For the purpose of allowing a user to explore a dataset consisting of many location-referenced image panoramas in an immersive manner, a responsive, intuitive user interface and a client-server architecture that minimizes user wait time are critical.

Process for displaying and navigating panoramic video, and method and user interface for streaming panoramic video and images between a server and browser-based client application

The Board of Trustees of the Leland Stanford Jr. University


An audio processing method utilized to generate an audio stream. An audio frame includes N frequency subbands. An Ith frequency subband among the N frequency subbands includes M audio samples and has an Ith psychoacoustic masking value. First, an Ith offset of the Ith frequency subband is calculated. Then, the Ith psychoacoustic masking value and the Ith offset are inputted into a projection formula to generate an Ith projection value. According to the Ith projection value and a limit range, an Ith scale factor is determined. Subsequently, the M audio samples in the Ith frequency subband are adjusted according to the Ith scale factor.

1. Field of the Invention
The present invention relates to a method for determining quantization parameters, particularly a method for determining quantization parameters in a bit allocation process.
2. Description of the Related Art
Since Thomas Alva Edison invented the gramophone, music has been playing an important role in people's lives. Because of people's demand of music, engineers keep on researching and have advanced the method to record and reproduce audio signals from the preliminary analog system to the presently popular digital system. Nowadays, CD (compact disc) is a popular format for storing audio signals. However, as the Internet continues to gain more popularity, the traditional format of CD music recordings is gradually replaced by some other coding algorithm formats, such as MPEG-audio Layer-3 or AAC (Advanced Audio Coding), because CD format recording generally has much more data size.
There are three steps in the traditional analog to digital music transforming process—Sampling, Quantization and Pulse Code Modulation (PCM). Sampling means reading the signal level of the music at each equal time interval. Quantization means representing the amplitude of each read signal in a quantization degree with a limited numerical value. Pulse Code Modulation (PCM) means representing the quantized value with a binary number. Traditional music CDs employ the aforementioned PCM technique to record analog music in the digital format, but it demands huge storage space and communication bandwidth. For example, nowadays music CDs adopt the 16 bits quantization degree. Therefore, it needs about 10 MB storage space for the music recording per minute. Due to the limited data transmission bandwidth for digital TV, wireless communication and the Internet, some encoding techniques for higher compression ratio on music signals are invented and developed.
Referring to FIG. 1, FIG. 1 shows a functional block diagram of an audio encoding system 10 of the prior art. Encoders, such as the aforementioned MPEG-audio LAYER-3 or AAC, encode a PCM sample into an audio bitstream of MPEG-audio LAYER-3 or AAC in the audio encoding system 10 in FIG. 1. The traditional audio encoding system 10 comprises a Modified Discrete Cosine Transform module (MDCT module) 12, a psychoacoustic module 14, a quantization module 16, an encoding module 18, and a bitstream packing module 19.
The PCM samples are inputted to both the MDCT module 12 and the psychoacoustic module 14, and the samples are first analyzed by the psychoacoustic module 14 to generate a masking curve and a window message. The masking curve delineates the range of audio signals to be perceived by ordinary human ears. Ordinary human ears can perceive only audio signals that are higher above than the masking curve.
According to the window message transmitted from the psychoacoustic module 14, the MDCT module 12 performs a modified discrete cosine transformation on the PCM samples. The PCM samples are transformed to a plurality of MDCT samples, and then the MDCT samples are grouped, according to the characteristic of human acoustic perception, to form a plurality of frequency subbands with non-equivalent bandwidth; each frequency subband is associated with a masking threshold. The quantization module 16 cooperates with the encoding module 18, repeatedly performing a bit allocation process on every frequency subband; such procedure ensures every MDCT sample in the frequency subbands conforms to the coding distortion standard. For instance, by means of a limited available bit numbers, the final encoding distortion of every MDCT sample is made to be lower than the corresponding masking threshold determined by the psychoacoustic module 14. After the bit allocation procedure, the encoding module 18 performs Huffman encoding on all MDCT samples in that frequency subband. Further, the bitstream packing module 19 combines all encoded frequency subbands, and packs all frequency subbands with corresponding side information so as to generate an audio bitstream, The side information contains information related to the entire audio encoding process, for example, window message, stepsize factor, Huffman encoding information, etc.
Referring to FIG. 2, FIG. 2 shows the flow chart of a conventional audio encoding. The conventional audio encoding such as MPEG-audio LAYER-3 (MP3) or AAC includes the following steps:
STEP 200: Start.
STEP 202: Receive PCM samples. Then go to step 204 and step 206.
STEP 204: Analyze the PCM samples using the psychoacoustic module to determine the corresponding masking curve.
STEP 206: Perform the modified discrete cosine transformation on the PCM samples to generate a plurality of MDCT samples which are grouped into several frequency subbands; each frequency subband may include different number of MDCT samples.
STEP 208: According to the masking threshold of each corresponding frequency subband, perform a bit allocation process on every MDCT sample in the frequency subband, so that the MDCT samples in the frequency subband conform to the encoding distortion standard.
STEP 210: Pack all of the encoded frequency subbands with the corresponding side information so as to generate a corresponding audio bitstream of the PCM samples.
STEP 212: End.
The bit allocation procedure performed by the quantization module 16 and the encoding module 18 in FIG. 1 further include many complicated steps. Referring to FIG. 3, FIG. 3 shows a flow chart of a conventional bit allocation procedure. The conventional bit allocation procedure includes the following steps.
STEP 300: Start.
STEP 302: Perform quantization of all the frequency subbands nonlinearly (disproportionately) according to a stepsize factor corresponding to each audio frame.
STEP 304: Look up the Huffman Table to calculate the number of bits needed by every MDCT sample of corresponding frequency subband.
STEP 306: Determine if the number of needed bits is lower than the number of available bits. If YES, go to STEP 310. If NO, go to STEP 308.
STEP 308: Increase the stepsize factor, and go back to STEP 302.
STEP 310: De-quantize the quantized frequency subbands.
STEP 312: Calculate the distortion of the frequency subbands.
STEP 314: Store the scalefactor of the frequency subbands and the stepsize factor of the audio frame.
STEP 316: Determine if there is any frequency subband with distortion exceeds the corresponding masking threshold. If NO, go to STEP 322. If YES, go to STEP 317.
STEP 317: Determine if there is any other termination condition met (such as the scalefactor has reached the upper limit); if YES, then go to STEP 318, if NO, then go to STEP 320.
STEP 318: Increase the value of the scalefactor.
STEP 319: Amplify all the MDCT samples of the frequency subband according to the scalefactor, and then go to STEP 302.
STEP 320: Determine if the scalefactor and the stepsize factor are better values or the most preferable values. If YES, then go to STEP 322. If NO, then go to STEP 321.
STEP 321: Restore previous better scalefactor and stepsize factor; then go to STEP 322.
STEP 322: End.
From the discussion above, there are two loops in the bit allocation procedure for determining the quantization parameter. The first loop is from STEP 302 to STEP 308; it is usually called the inner loop or the bit rate control loop, used for determining the stepsize factor. The second loop is from STEP 302 to STEP 322; it is usually called the outer loop or the distortion control loop, used for determining the scalefactor. Thus, each run of the traditional bit allocation method usually requires many runs of the outer loop, and every outer loop includes many runs of the inner loop. Such replicated operation leads to poor efficiency of the prior art. To improve the encoding efficiency, reducing the number of the loops and operations becomes important. Besides, since the bit allocation loop of the prior art only increments one to the stepsize factor each time, it causes the increase of the repeated operation of the bit-rate control loop.
Some Related Information are Listed for Reference.
[1] Information technology—coding of moving pictures and associated audio for digital storage media at up to about 1.5 Mbit/s. part 3: Audio. Technical report, ISO/IEC, MPEG 11172-3, 1993.
[2] Information technology—generic coding of moving pictures and associated audio information. Part 3: Audio. Technical report, ISO/IEC MPEG 13818-3, 1998.
[3] Information technology—generic coding of moving pictures and associated audio information. Part 7: Advanced audio coding (AAC). Technical report, ISO/IEC MPEG 13818-7, 1997.
[4] Information technology—very low bitrate audio-visual coding. Part 3: Audio. Technical report, ISO/IEC MPEG 14496-3, 1998.
[5] US2001/0032086 A1, Fast convergence method for bit allocation stage of MPEG audio layer 3 encoders.
[6] EP 0967593 B1, Audio coding and quantization method.
[7] H. Oh, J. Kim, C. Song, Y. Park and D. Youn. "Low power MPEG/audio encoders using simplified psychoacoustic model and fast bit allocation. IEEE transactions on Vol. 47, pp. 613-621, 2001.
[8] C. Liu, C. Chen, W. Lee and S. Lee. "A fast bit allocation method for MPEG layer III". Proc. of ICCE, pp.22-23, 1999.
[9] Alberto D. Duenas, Rafael Perez, Begona Rivas, Enrique Alexandre, Antonio S. Pena. "A robust and efficient implementation of MPEG-2/4 AAC Natural Audio Coders". In AES 112th Convention, 2002.

Audio processing method for generating audio stream


A process for the production of polycarbonate having increased end-cap levels, the process comprising adding a terminal blocking agent of the formula:

Polycarbonate is a thermoplastic that has excellent mechanical properties (e.g., impact resistance), heat resistance and transparency. Polycarbonate is widely used in many engineering applications. It is known that a high level of end-capping, (i.e., wherein most of the terminal phenolic hydroxyl groups in the polycarbonate are reacted with monofunctional endcapping agents to form relatively inert polymer chain ends) helps to reduce static, improve heat aging, and reduce water absorption. Consequently, various coupling agents and end-cappers have been used to enhance the end-cap levels in the production of polycarbonate.
Unexamined Japanese Patent Application H6-157739 discloses the use of certain non-activated carbonates (e.g., diphenyl carbonate) and esters as end-capping agents.
Japanese Patent Application JP-A 7-90074 discloses a method of producing a polycarbonate from a dihydric compound and a carbonic acid diester by an ester exchange method. In this method, a highly active diester, acid halide or acid anhydride with at least two functional groups is added after the ester exchange ratio exceeds 70% to obtain a polycarbonate having an enhanced degree of polymerization. It should be noted that JP-A 7-90074 teaches the use of de-activated molecules as coupling agents or polymerization promoters, and not end-cappers.
U.S. Pat. No. 5,696,222 and European Application No. EP 0 985 696 A1 disclose a method of producing a polycarbonate having a high-end cap levels by adding certain activated and bis-activated carbonates as end-cappers. It is disclosed that the end-capping agents are added to the process after the polycarbonate formed has an intrinsic viscosity of at least 0.3 dl/g. The resulting polycarbonate has increased end-cap levels with minimal changes in molecular weight or intrinsic viscosity (i.e., it has an intrinsic viscosity that is greater or smaller than the viscosity of the polycarbonate formed before the addition of the end-cappers by at most 0.1 dl/g). It is also disclosed that these end-cappers are activated by a phenolic group having an ortho chlorine atom, methoxycarbonyl or ethoxycarbonyl group. These end-cappers are high melting point solids, and thus require complicated and energy intensive apparatus comprising melting vessels and heated feeding lines for accurate and controlled feeding of the end-capper to the polycarbonate.
EP 0 980 861A1 discloses the use of certain salicylic acid ester derivatives as terminal blocking agents in amounts of 0.1 to 10 times, and most preferably 0.5 to 2 times, mole per mole equivalent of terminal hydroxyl groups of the polycarbonate formed at a time of the addition. Such polycarbonates have good color tone suitable for optical material use. It is disclosed that these end-cappers are activated by a phenolic group having an ortho methoxycarbonyl or ethoxycarbonyl group. It should be noted that the Examples of EP 0 980 861A1 teach the use of 2-methoxycarbonylphenyl-phenylcarbonate as an end-capper in an amount that is about 1 mole per mole equivalent of terminal hydroxyl groups to form a polycarbonate with increased end-cap levels.
There is still a need for an improved melt process using easy to handle low melting end-cappers to produce polycarbonate having capped terminals and controlled molecular weight.

Process for the production of polycarbonate

Abstract: wherein R1 is a propoxy or butoxy and R2 is selected from the group consisting of C1-C30 alkyl, C1-C30 alkoxy, C6-C30 aryl, C7-C30 aralkyl, and C6-C30 aryloxy.


Methods and compositions that provide for the long-term adhesion and slow-release of various bioactive agents on the surface of human skin utilize siloxane bridging agents activated for reaction with the skin surface which bind the bioactive agent to the skin surface. Since the topical agent remains bound to the continuously renewing epidermis, safety is enhanced for many bioactive agents. Slight modifications of the siloxane bridging compounds or bioactive agents allows for more or less adhesion to the skin, controlling the degree of release of the agent. Skin treatments according to the invention can provide enhanced repellency to microorganisms, insect bites, sun, water, poison ivy/oak, and other skin irritants, and other effects such as artificial skin coloring and administration of topical drugs, among others.

Many bioactive topical agents, such as sunscreens, moisturizers, repellents, antimicrobials, and other pharmaceuticals, are intended for use on the surface of human skin. Such agents are generally effective only as long as the agent persists on the skin. As a result, however, of normal daily activities, for example, perspiring, washing, or wearing clothes, a topical agent loses its activity due to premature removal. Despite recognition of this substantivity problem, i.e., the problem of significantly sustained presence of the topical agent, no satisfactory solution has been proposed in the prior art.
Attempts to prolong substantivity of a topical agent have focused on developing compositions which incorporate excessive amounts of water-insoluble materials. These formulations result in cosmetically undesirable surface coatings and occlusion of the skin, yet do not substantially enhance the substantivity of the bioactive agent. Many commercially available topical formulations consist of an oily carrier of base such as mineral oil or a fatty acid ester, or a polymeric carrier or base such as polymethacrylate or polydimethylsiloxane which is insoluble or nearly insoluble in water, plus a bioactive agent (e.g., an ultraviolet-absorbing or antimicrobial agent). Such compositions tend to be greasy, tacky, occlusive (cause excess perspiration), and also tend to stain clothing. These water-insoluble compositions only provide minimal wash-resistance and do little to control the release of the bioactive agent either off of the skin or into the blood. Alternative attempts to prolong substantivity of topically delivered bioactive agents have focused on developing band aid-like patches. This approach is cosmetically undesirable.
There has been considerable interest in the use of organopolysiloxane compounds as surface agents. Organopolysiloxanes exhibit a broad spectrum of properties depending on molecule size, side-chain group type, and the degree of cross-linking between chains. These polymers, which are predominantly polymethylsiloxanes and polymethylphenylsiloxanes, are generally safer and more resistant to attack by temperature, sun, water, ozone, chemicals, corona discharge, dirt, and shear than their carbon counterparts. As a result, many of these polymers have been used as surface protective agents for inanimate substrates. For example, silicones have been used as insulators in high temperature electric machines, as lubricants for high stress, shear, and temperature environments, and as weather protection and water repellency treatments for masonry, leather, textile, paper, metal, and glass surfaces. See, for example, W. Noll, Chemistry and Technology of Silicones, Chapter 10, Academic Press, 1968.
Fully polymerized siloxane compounds have also been used in the formulation of cosmetics, pharmaceuticals, and artificial implants. General inertness, high performance under stress, and specific ability to retard blood clotting are key qualities of silicone biological implants. In cosmetic and pharmaceutical formulations for skin applications, polysiloxanes are typically used as the carrier (or part of the carrier) to provide a non-greasy, low vapor pressure, inert matrix for the bioactive ingredient. Polysiloxanes have been used, for example, (1) to provide a water-insoluble, low vapor-pressure matrix for insect repellents as described in Kauppi U.S. Pat. No. 2,681,878, issued Jun. 22, 1954 and for skin protectants as described in Morgulis U.S. Pat. No. 2,698,824, issued Jan. 4, 1955; (2) to provide a non-greasy cosmetic formulation as described in Kass U.S. Pat. No. 3,392,040 issued Jul. 9, 1968; (3) to provide a non-tacky cosmetic formulation as described in Clum et al. U.S. Pat. No. 4,423,041 issued Dec. 27, 1983; and (4) to provide a non-irritating matrix for topical agents as described in Starch U.S. Pat. No. 4,311,695, issued Jan. 19, 1982. These preparations involve polymerization of the siloxane compounds prior to skin contact.
Other silicon-based compounds known as silane coupling agents are used as adhesives for bridging dissimilar materials. Methods for preparing silane coupling agents, also called polymerizable silanes and hydrolyzable silanes, and use of such compounds to provide adhesion between dissimilar inanimate materials such as glasses, metals, textiles, and composite polymers, is well known. See, for example, E. P. Plueddmann, Silane Coupling Agents, Plenum Press, 1982.
The use of silane coupling agents with biomaterials is more recent. Enzymes and proteins have been immobilized on silanized glass. See for example, D. E. Leyden and W. Collins, Silylated Surfaces, Gordon and Breach, 1980, pp. 189, 201, 363. The technique typically involves silylation of porous glass using .gamma.-aminopropyltriethoxysilane, i.e., modification of the glass surface with a polymerizable silane, followed by enzyme/protein reaction with the amine of the aminopropyl glass. This provides a means to effect analytical separation and purification of antibodies and enzymes.
Silane coupling agents have also been used along with other polymers to create cross-linked polymer meshes and cages which typically entrap a biogenic agent such as an insecticide or microbiocide. See, for example, Young et al. U.S. Pat. Nos. 4,172,904 issued Oct. 30, 1979; 4,200,664, issued Apr. 29, 1980; 4,500,337, issued Feb. 19, 1985; 4,500,338, issued Feb. 19, 1985; and 4,500,339, issued Feb. 19, 1985. Such physical entrapment using acrylic polymers for skin topicals has also been described. See, for example, Kubik et al. U.S. Pat. No. 4,172,122 issued Oct. 23, 1979 (sunscreens), and Randen U.S. Pat. No. 4,552,755, issued Nov. 12, 1985 (moisturizing compositions).
Sunscreen formulations have been prepared using silane coupling agents which are polymerized prior to skin contact. See, for example, Morehouse U.S. Pat. Nos. 2,929,829, issued Mar. 22, 1960 and 3,068,153, issued Dec. 11, 1962; Bailey et al. U.S. Pat. No. 2,950,986, issued Aug. 30, 1960; and Black U.S. Pat. Nos. 2,973,383, issued Feb. 28, 1961 and 3,068,152, issued Dec. 11, 1962. Typically, these compositions involve the preparation of a silane coupling agent modified with a sunscreen, followed by formulation into a water-containing base. Specific examples include the preparation of two p-aminobenzoic acid (PABA) derivatives (one via amide derivatization of the PABA-amine and one via amide derivatization of the PABA-carboxyl) and one benzophenone derivative (a sulfonic acid salt) that carry the triethoxysiloxane group (a polymerizable oxysilane). These materials are then formulated into an aqueous solution or creme for end use. The method of formulation incorporates substantial amounts of water (and in most cases, heat as well) which causes polymerization of the silane coupling agent prior to use on the skin.
Ideally, a topical agent should possess several characteristics in order for the bioactive agent to work effectively, efficiently, and safely. It should be non-toxic and without side effects, non-irritating, non-greasy, tackless, odorless, invisible, non-staining, easy to apply, and not easily removed by normal activities so it will provide full bioactive functionality for extended time periods (i.e., 1-7 days). The present invention provides topical agents which have these characteristics to a greater extent than many prior preparations.

Bioactive topical siloxane compositions having enhanced performance and safety


An electrophysiology catheter assembly having a deflection mechanism rotatably disposed within an inner lumen of the catheter so that deflection of the deflection mechanism within the inner lumen results in a deflection of the distal portion of the catheter. Rotation of the deflection mechanism within the inner lumen of the catheter allows universal deflection of the distal portion of the catheter about its longitudinal axis. The deflection mechanism may be first rotated and then deflected or it may be first deflected and then rotated in a deflected condition. The catheter shaft does not need to be rotated to change the shape of its distal portion.

This invention relates to intraluminal catheters and particularly to electrophysiology (EP) catheters having distal tips which are shapable after insertion to a patient's body lumen.
EP catheters generally have elongated catheter shafts with one or more electrodes on their distal ends to detect electrical activity or to emit high frequency, e.g. RF, electrical energy, to ablate tissue within a patient's body. Such catheters have been used to detect electrical activity within a patient's heart to determine the location of tissue causing arrhythmia, and to ablate tissue causing arrhythmia once the location of the tissue causing the arrhythmia has been determined.
The distal extremities of EP catheters frequently need to be deflected or shaped within the patient in order to guide the distal extremity into a desireable body lumen or chamber. For example, it is very difficult to advance an EP catheter into a patient's coronary sinus from the inferior vena cava. In other instances it is desireable to shape the distal extremity of an EP catheter to more closely conform the shape of the distal extremity to the patient's endocardium when detecting electrical activity. It is also desireable to shape the distal extremity of an ablation type catheter to orient the distal tip thereof with respect to tissue, such as a patient's endocardium, to facilitate proper delivery of RF energy, laser energy and the like. U.S. Pat. No. 5,190,050 (Nitzche) is an example of an EP type catheter with a deflectable distal tip.
The prior catheters which have a deflection mechanism are usually limited to uniplanar deflection which requires the catheter shaft to be rotated from its proximal end located outside of the patient in order to place the deflected tip into a desired plane, e.g. to seat the distal tip of the catheter into a desired branch of a blood vessel. Unfortunately, the torque applied at the proximal end does not always result in the same rotation at the distal end. Frequently, the catheter shaft will store up the torque and then suddenly release the stored up torque, causing the distal end to suddenly rotate, i.e. whip. Providing a catheter shaft with sufficient strength to transmit to the distal end torque which is applied to the proximal end can increase the stiffness of the shaft to the extent that advancement through tortuous anatomy is difficult.
What has been needed and has heretofore been unavailable is an EP type catheter which has a distal tip with the capability for universal deflection from its longitudinal axis without requiring the entire catheter to be rotated from its proximal end. The present invention satisfies these and other needs.

Catheter with deflectable distal section


Information in the form is analyzed based on adjacency relationships among cells in the forms. By using adjacency relationships, a format may be provided for forms which are divided into cells by separators such as lines, notwithstanding that the positions and sizes of the cells may change, as long as their order remains unchanged. In particular, cells are extracted from the image data of a form. Adjacency relationships among the extracted cells are determined. The determined adjacency relationships are compared with a set of adjacency relationships are compared with a set of adjacency relationships in order to identify the extracted cells. Information contained in the form is then recognized based upon the identified extracted cells. In particular, the information contained in the form is recognized, based upon the identified cell in which the information is contained.

Forms are widely used in many consumer and commercial environments. Presently, forms are being processed by computers to enhance efficiency. As used herein, a form is a particular type of document. A form has a number of horizontal and vertical separators such as lines therein. Regions surrounded by these lines are called cells. A cell may be a region previously printed on the form itself such as "Name" (a header field), or a text field in which a user specifically fills in his or her name or address. These fields are laid out on the form in a predefined layout.
Generally, a system which processes a form captures an image of the form (bitmap) using a reader device such as an OCR so that the form processing system can extract necessary information from the form. The layout of the form is determined by analyzing the image on the basis of a format previously stored in the memory of the computer system. The format is a model for analyzing the layout of form. The layout of the form is analyzed by referring to this model for comparison. The analysis enables the system to identify what information such as an address or name exists at a predefined position on the form, and to recognize images of characters, numbers and symbols actually existing at that position as text by using well known character recognition techniques. This allows the system to recognize the information filled in that position as a text.
A simple conventional format is defined on the basis of positions and length of lines previously printed on the form, and characters previously printed (headers). In other words, the format is a blank form in which nothing is entered. Based on such a format, the blank form is erased from the bitmap of the form actually read by the reader device, and analyzed for the layout of the form. Thus, information on the form is identified.
FIG. 1 shows samples of specific forms. These three samples A, B and C differ from each other in the positions and length of lines therein. Conventionally, forms which can be handled with one format are generally limited to those in which positions and lengths of lines existing in the form exactly match the information of the format. Thus, the layout of the three samples of FIG. 1, generally cannot be readily analyzed with one format. Therefore, different formats corresponding to each of the samples A, B and C are generally provided. Since the memory area for storing data of respective formats may increase, excessive memory may be used. In addition, every time the form processing system receives a form, it may need to verify to which form it corresponds, so that the speed for processing the form may decrease. The decrease in processing speed may become significant as the number of forms to be processed increases.
In order to make it possible to accommodate a plurality of different forms which have different layouts with a single format, a technique has been proposed which defines a format based on an order of drawing lines in the form instead of using strict matching of positions or length of lines as the reference. In the sample B of FIG. 1, for example, the entire form is first divided into upper and lower areas by traversing it (Line 1). Then, the divided upper and lower areas are further vertically divided (Lines 2 and 3), so that the upper area is divided into a "Name area" and a "Zip area," and the lower area is divided into an "Address area" and a "Phone area." Furthermore, respective areas are vertically divided into a header area and a text field (Lines 4, 5, 6, and 7).
The format for sample B which is defined by the order of line drawing in the form, can be applied to a form in which the Line 5 in FIG. 1(B) is replaced with a Line 5', because the order of line drawing is unchanged. However, this format generally cannot be applied to the sample C in which the order differs from that for the sample B. In the case of sample C, the entire form is first vertically divided (Line 1) so that the form is divided into two right and left areas. Then, the divided right and left areas are horizontally divided (Lines 2 and 3).
Since the forms of FIGS. 1(B) and (C) differ from each other in the order of line drawing, they generally are represented by different formats. Therefore, this approach may not handle the three samples shown in FIG. 1 with a single format. In addition, when a format is produced from an actual form, or when a format is updated with a new form, expertise may be necessary to perform such operation.

Methods, systems and computer program products for analyzing information in forms using cell adjacency relationships

International Business Machines Corporation


A device for converting heat into electrical power. The device comprises a base made of a heat conducting material. The base has a substantially flat bottom surface for being placed onto a flat outside surface of a heat source. At least a thermoelectric generator element is disposed onto a top surface of the base such that a high temperature surface of the thermoelectric generator element is in thermal contact with the top surface of the base. A heat sink structure is in thermal contact with a low temperature surface of the at least a thermoelectric generator element. Electrical circuitry is connected to the at least a thermoelectric generator element for receiving the electrical power therefrom. At least an electrical output port is connected to the electrical circuitry for providing the electrical power.

These days pellet stoves are increasingly used as a main home heating source. A typical pellet stove comprises a compartment to store pellets therein and a conveying mechanism for conveying the pellets to a combustion chamber. The pellets are ignited manually or with a heating element. A blower circulates air through a heat exchange apparatus or around the combustion chamber which is then expelled into the surrounding environment of the pellet stove.
Conventional pellet stoves rely on a reliable outside electrical power source for operating the conveying mechanism, the blower and, optionally, the heating element for initially igniting the pellets and can only ensure continued operation for a very short period of time during emergency power-outages. Therefore, the conventional pellet stove cannot be operated off-grid or during power outages. Furthermore, provision of outside electrical power typical adds cost to the operation of the pellet stove and requires an electrical outlet placed nearby, which may require rewiring of the home when newly installing a pellet stove.
In an attempt to overcome this drawback of the conventional pellet stoves, Landon teaches in U.S. Patent Application Pub. No. US 2007/0221205 "self-powering" technology.
Unfortunately, this technology is designed to be built into the pellet stove during manufacturing in close proximity to the combustion chamber and is, therefore, unsuitable as a retro-fit to existing pellet stoves.
It is desirable to provide a device for converting heat into electrical power that is simple and suitable as a retro-fit to existing stoves.
It is also desirable to provide a device for converting heat into electrical power that is easy to install as a retro-fit to existing stoves.
It is also desirable to provide a device for converting heat into electrical power that is capable of powering a pellet stove and further electrical devices.

Device for converting heat into electrical power


A secondary window includes a first glazing, a film, and a first frame. The first glazing includes a glass substrate having a thickness, between a first glazing surface opposite a second glazing surface, less than 2.0 millimeters. The film is attached to the first glazing surface. The first glazing is secured in the first frame, which at least partially surrounds the glazing. A second secondary window includes a second glazing secured in a second frame, which at least partially surrounds the second glazing. The second glazing includes (a) a first pane having a first-pane thickness less than 2.0 millimeters and (b) a second pane having a second-pane thickness that exceeds the first-pane thickness.

Many older commercial and residential buildings still have their original single-pane windows, which provide far inferior thermal insulation compared to new replacement windows. While single-pane windows increase heating and/or cooling costs for such buildings, replacing the single-pane windows with newer energy-efficient windows can be cost-prohibitive. For example, recouping the cost of new windows with lower energy bills may take decades. Furthermore, replacing original windows may be undesirable for aesthetic reasons, e.g., for historical buildings, for which building codes may also prohibit modification of the building's external appearance.
Secondary windows, also known as window inserts, provide an alternative to window replacement. A secondary window may be installed adjacent to the interior side of a building's existing window, which is known as a primary window. Many tall single-glazed buildings cannot be retrofit with a second pane of standard-width glass due to civil engineering limitations, structural limitations, and weight limitations. Other problems with existing secondary windows include: fragility, requirement of thick perimeter framing, high cleaning costs, and relatively high coefficients of thermal expansion, which results in poor surface-flatness that distorts visible scenes outside of the window.


The present invention relates to the field of toys, and more specifically, to a magnet-mounted part for mounting a magnet and a magnet toy. Particularly, the present invention provides a magnet-mounted part comprising: a magnet mounting unit on which a magnet is mounted, and which has a saw-toothed wheel engaged with the magnet-mounted part on which an external magnet is mounted, an accommodation unit which accommodates the magnet-mounted unit therein, and has an opening portion such that the saw-toothed wheel of the magnet-mounted unit can be exposed; and a One rotation angle-adjusting unit which is provided to rotate in engagement with the magnet-mounted unit and the accommodation unit, and is formed such that the unit rotation intervals thereof are smaller than the toothed intervals of the saw-toothed wheel of the magnet-mounted unit.

In recent time, various types of magnet toys, as toys for encouraging creativities of infants or small children, are developed such that the children can assemble several blocks using magnets to joyfully make buildings, cars, robots and the like.
The magnet toy is basically configured in a manner of mounting a magnet onto each surface of a toy main body such that toys can be freely assembled to each other by a mutual attachment (attraction) between the magnets.
However, the magnetic coupling using the magnets is merely achieved by a surface-to-surface contact between blocks. Accordingly, the coupling is instable. Consequently, the magnet-mounted toys may have several disadvantages of, for example, easy destroy while assembling the toys or playing with a completely-assembled toy, being tired of easily disassembled or destroyed toys depending on ages, and the like.
Therefore, a method of more inspiring creative abilities of infants is continuously required.

Magnet-mounted parts and magnet toy including same


A novel trivalent Group IVB metal complex for preparing syndiotactic vinyl aromatic polymers is disclosed which is coordinated by a bidentate ligand and is represented by the formula (I): EQU (C.sub.5 R.sub.n H.sub.5-n)M(BD).sub.m Y.sub.p (I). wherein C.sub.5 R.sub.n H.sub.5-n is a substituted or unsubstituted cyclopentadienyl group, n is an integer between 0 and 5, and R is C.sub.1 to C.sub.12 alkyl, aryl, substituted alkyl, or substituted aryl; M is a trivalent Group IVB metal; (BD) is a bidentate ligand with -1 valence, having a coordinating group which is capable of forming a coordinating bond or a chelating bond with the metal M; Y is selected from the group consisting of alkyl, aryl, aralkyl, halogen and hydrogen; m is an integer of 1 or 2; and m+p=2.

1. Field of the Invention
The present invention relates to a novel bidentate coordinated trivalent Group IVB metal complex, and, more particularly, to a process for preparing syndiotactic vinyl aromatic polymers using the bidentate coordinated trivalent Group IVB metal complex as a catalyst.
2. Description of the Prior Art
Vinyl aromatic polymers, or vinyl aromatic compound-containing polymers in general, can be classified into three categories: atactic, isotactic, and syndiotactic. The vinyl aromatic polymers having a syndiotactic configuration have many advantageous properties than the atactic and isotactic counterparts. For example, syndiotactic polystyrenes exhibit the advantages of having high melting point (about 270.degree. C.), low density (about 1.04 kg/cm.sup.3), low dielectric constant (about 2.6), high vicat softening temperature (about 254.degree. C.), excellent chemical resistance and water (steam) resistance, and low moisture absorption. The above reported values are measured from a specific syndiotactic polystyrene under a specific set of conditions. These values, of course, are subject to change as a result of different polymer molecular weight and many other factors.
In recent years, a trivalent titanium-based catalyst containing cyclopentadienyl as a ligand has been used for preparing syndiotactic vinyl aromatic polymers. For example, WO 95/10551 discloses a trivalent titanium-based catalyst composition for preparing syndiotactic vinyl aromatic polymers. Such catalyst composition includes pentamethylcyclopentadienyl titanium (III) dimethoxide Cp*Ti(OMe).sub.2, in which Cp* represents pentamethylcyclopentadienyl and Me represents methyl!, a borate, and a hydrocarbylation agent. In addition, European Patent No. 0,655,467 discloses the use of another trivalent titanium-based catalyst for preparing vinyl aromatic polymers.
However, the above-mentioned catalysts suffer from a number of shortcomings in that the catalyst has undesirable catalytic activity, inferior stereoselectivity, and the polymer so obtained exhibits an undesirably broad molecular weight distribution.

Bidentate coordinated trivalent Group IVB metal complex catalyst for preparing syndiotactic vinyl aromatic polymer

Industrial Technology Research Institute