An air conditioning and dehumidifier system (310) comprising: an air conditioner (312) comprising a cooling unit, a first inlet (316) to the cooling unit drawing air from a controlled area (314); a second inlet (338) to the cooling unit drawing fresh air firm outside the area (314); an outlet (324) to the area (314); a condenser (328) with an air inlet (330) into which relatively cool outside air is drawn; and a heated air outlet (334) from the condenser (328); a dehumidifying unit (342) utilizing liquid desiccant, comprising a drying unit (344) having a wet air inlet (346) and dry air outlet (348); a regenerator unit (350); a hot air inlet (352); a wet air outlet (354); and a heat pump that transfers heat from relatively cooler liquid desiccant to relatively warmer liquid desiccant; a conduit connecting the heated air outlet (334) of the air conditioner (312) to the hot air inlet (352) of the dehumidifying unit (342); and a conduit (349) connecting the dry air outlet (348) of the dehumidifying unit (342) to the second inlet (338) of the air conditioner (312).

The present invention is related to the field of environmental control systems and more particularly, to the field of systems which combine dehumidification and air conditioning.
In general, air conditioning systems not only reduce the temperature of the ambient air, but also remove substantial amounts of water from it. This is especially true when the air conditioner is treating xe2x80x9cfreshxe2x80x9d air inputted from outside the controlled environment. However, such combined air conditioning/dehumidification is generally inefficient. Furthermore, since some of the potential cooling power of the air-conditioner is used for dehumidification, the effective cooling capacity of the air conditioner is significantly reduced.
It is known in the art to provide dehumidification of air prior to its being cooled. In some cases, the mechanisms of the dehumidifier and the air conditioner are not integrated. In such cases, while there is an increase in the cooling capacity of the air conditioner, the overall efficiency of the system is relatively poor.
U.S. Pat. No. 4,984,434 describes an integrated system in which air to be cooled is first dehumidified by passing it through a desiccant type dehumidifier before being cooled by contact with an evaporator of an air conditioner. Regeneration of the desiccant is performed by passing the water containing desiccant over the condenser of the air conditioning system.
This system suffers from a number of limitations. Firstly, it dehumidifies all of the air being cooled. Since most of the air inputted to the dehumidifier is from the controlled space (and thus fairly dry already) the dehumidifier does not remove much water from the air and thus does not provide much cooling for the condenser. This would cause an overall increase in the temperature of the desiccant and a reduction in the efficiency of both the dehumidifier and the air-conditioner. A second problem is that such a system is not modular, namely, the dehumidifier must be supplied as part of the system. Furthermore, adding a dehumidifier to an existing air conditioning system and integrating the dehumidifier and air conditioner to form the system of this patent appears to be impossible.
Another type of dehumidifying/air conditioning system is also known. In this type of system, as described, for example in U.S. Pat. Nos. 5,826,641, 4,180,985 and 5,791,153, a dry desiccant is placed in the air input of the air-conditioner to dry the input air before it is cooled. Waste heat (in the form of the exhaust air from the condenser) from the air conditioner is then brought into contact with the desiccant that has absorbed moisture from the input air in order to dry the desiccant. However, due to the relatively low temperature of the air exiting the air conditioner, the amount of drying available from the desiccant is relatively low.
The above referenced U.S. Pat. No. 4,180,985 also describes a system using liquid desiccant as the drying medium for the dehumidifying system. Here again, the low temperature of the exhaust as from the air conditioner reduces substantially the efficiency of the system.
Prior art desiccant based dehumidifiers generally require the movement of the desiccant from a first region in which it absorbs moisture to a second regeneration region. In the case of solid desiccants, this transfer is achieved by physically moving the desiccant from a dehumidifying station to a regeneration station, for example by mounting the desiccant on a rotating wheel, a belt or the like. In liquid desiccant systems two pumps are generally provided, one for pumping the liquid to the regeneration station and the other for pumping the liquid from the regeneration station to the dehumidifying station. In some embodiments, a single pump is used to pump from one station to the other, with the return flow being gravity fed.
The operation of standard air conditioning systems and the desiccant systems described above is illustrated with the aid of FIG. 1. FIG. 1 shows a chart of temperature vs. absolute humidity in which iso-enthalpy and iso-relative humidity curves are superimposed. Normal air conditioners operate on the principle of cooling the input air by passing it over cooling coils. Assuming that the starting air conditions are at the spot marked with an X, the air is first cooled (curve 1) until its relative humidity is 100% at which point further cooling is associated with condensation of moisture in the air. In order for there to be removal of liquid from the air, it must be cooled to a temperature that is well below a comfort zone 4. The air is heated to bring it to the comfort zone, generally by mixing it with warmer air already in the space being cooled. This excess cooling in order to achieve dehumidification is a major cause of low efficiency in such systems, under certain conditions.
Normal dehumidifier systems actually heat the air while they remove air from it. During dehumidification (curve 2) the enthalpy hardly changes, since there is no removal of heat from the system of air/desiccant. This results in an increase in temperature of both the desiccant and the air being dried. This extra heat must then be removed by the air conditioning system, lowering its efficiency.
In all dehumidifier systems mechanical power must be exerted to transfer the desiccant in at least one direction between a regenerating section and a dehumidifying section thereof. For liquid systems, pumps are provided to pump liquid in both directions between the two sections or between reservoirs in the two sections. While such pumping appears to be necessary in order to transfer moisture and/or desiccant ions between the two sections, the transfer is accompanied by undesirable heat transfer as well.
An aspect of some preferred embodiments of the invention is concerned with a combined dehumidifier/air conditioner is which a relatively low level of integration is provided. In preferred embodiments of the invention, heat generated by the condenser is used to remove liquid from the desiccant. However, unlike the above referenced prior art, the air conditioner condenser continues to be cooled by outside air. The heated air which exits the air-conditioner, containing waste heat, is used to remove moisture from the desiccant.
In contrast to the prior art, in which the heated air is the sole source of energy for the regeneration of the desiccant, in preferred embodiments of the invention, a heat pump is utilized to transfer energy from relatively cool desiccant to heat the desiccant during regeneration, in addition to the heat supplied from the exhaust of the air conditioning portion of the system. This results in a system in which the air conditioner does not have to overcool the air to remove moisture and the dehumidifier does not heat the air in order to remove moisture. This is in contrast with the prior art systems in which one or the other of these inefficient steps must be performed.
In some preferred embodiments of the invention combined dehumidifier/air-conditioner in which only xe2x80x9cfreshxe2x80x9d, untreated air is subject to dehumidification prior to cooling by the air conditioner. This allows for both the dehumidifier and the air-conditioner to operate at high efficiency, since the dehumidifier will be operating on only wet xe2x80x9cfreshxe2x80x9d air and the air conditioner will be cooling only relatively dry air.
Thus, in preferred embodiments of the invention, the amount of waste heat generated by the air-conditioner is relatively high and the heat requirements of the dehumidifier are relatively low, since a major portion of the heat for regeneration is supplied by the heat pump.
According to an aspect of the invention a simple method of integration of an air conditioner and dehumidifier is provided. In accordance with a preferred embodiment of the invention, the air conditioner and dehumidifier are separate units without conduits for air connecting the units. However, unlike prior art unintegrated units, the present invention provides advantages of utilizing waste heat from the air conditioner to provide regeneration energy for the dehumidifier.
According to an aspect of some preferred embodiments of the invention, in the steady state, moisture is transferred from the dehumidifier portion of a system to the regenerator without the necessity of transferring liquid from the regenerator back to the dehumidifier.
In general, in liquid dehumidifier systems, moisture must be transferred from the dehumidifier section to the regenerator section. Since the moisture is in the form of a moisture rich (low concentration) desiccant, this is performed by pumping or otherwise transferring the desiccant. Since the desiccant also contains desiccant ions, these must be returned to the dehumidifier to maintain the desiccant ion level required for dehumidification. This is generally achieved by pumping high concentration desiccant from the regenerator to the dehumidifier section. However, in addition to pumping ions, moisture is also transferred. While the extra energy utilized for pumping may or may not be significant, the inadvertent heat transfer implicit in pumping of the moisture back to the dehumidifier is significant in reducing the efficiency of the system.
In a preferred embodiment of the invention, reservoirs in the dehumidifier and regenerator sections are connected with a passageway that allows only limited flow. Preferably, the passageway takes the form of an aperture in a wall common to the two reservoirs.
During operation, the absorption of moisture in the dehumidifying section increases the volume in the dehumidifier reservoir, resulting in the flow, by gravity, of moisture rich (low concentration) desiccant from the dehumidifier reservoir to the regenerator reservoir. This flow also carries with it a flow of desiccant ions, which must be returned to the dehumidifier section. As indicated above, in the prior art, this is achieved by pumping ion rich desiccant solution from the regenerator to the dehumidifier section. In a preferred embodiment of the invention, the return flow of ions is achieved, by diffusion of ions, via the aperture, from the high concentration regenerator reservoir to the low concentration reservoir. The inventors have found that, surprisingly, diffusion is sufficient to maintain a required concentration of ions in the dehumidifier section and that the return flow is not associated with an undesirable heat transfer associated with the transfer of (hot) moisture together with the ions, as in the prior art.
In especially preferred embodiments of the invention, no pumps are used to transfer desiccant between the reservoirs or between the dehumidifier section and the regenerator, in either direction.
There is thus provided, in accordance with a preferred embodiment of the invention, an air conditioning and dehumidifier system for controlling the environment of a controlled area, comprising:
an air conditioner comprising:
a cooling unit in which air is cooled;
a first inlet to the cooling unit drawing air from the area;
a second inlet to the cooling unit drawing fresh air from outside the area;
an outlet to the area via which cooled air is transferred to the area;
a heat exchanger at which heat removed from air by the cooling unit is removed from the air conditioner;
an air inlet to the heat exchanger into which relatively cool outside air is drawn, heat being transferred to said air from said heat exchanger; and
a heated air outlet from the heat exchanger from which the heated air exits;
a dehumidifying unit utilizing liquid desiccant, comprising:
a drying unit having a wet air inlet and a dry air outlet from which air dried by the drying unit exits and in which liquid desiccant dries the air and removes heat from it;
a regenerator unit in which moisture removed from air by the drying unit is removed from the liquid desiccant;
a hot air inlet to the regenerator unit;
a wet air outlet from the regenerator unit via which air entering the hot air inlet exits after moisture is transferred to it; and
a heat pump that transfers heat from relatively cooler liquid desiccant in the dehumidifying unit to relatively warmer liquid desiccant;
a conduit connecting the heated air outlet of the air conditioner to the hot air inlet of the dehumidifying; and
a conduit connecting the dry air outlet of the dehumidifying unit to the second inlet of the air conditioner.
Preferably, moisture removal from the desiccant is aided by providing heat to the regenerator.
In a preferred embodiment of the invention, the system includes at least one pump to pump desiccant between the driving unit and the regenerator.
Preferably, the relatively cooler liquid desiccant is in a dehumidifier sump that receives desiccant after it has absorbed moisture from the outside air.
Preferably, the drying unit comprises a chamber in which said moisture is removed from the outside air and wherein the heat is removed by the heat pump from liquid desiccant being transported to the chamber. Preferably, the drying unit comprises a dehumidifier sump that receives desiccant after it has absorbed moisture from the outside air and wherein the heat is removed by the heat pump from liquid desiccant being transported to the chamber from the sump.
In a preferred embodiment of the invention, the regenerator unit comprises a compartment that contains liquid desiccant being regenerated and wherein the heat is transferred directly by the heat pump to said desiccant in said compartment.
Preferably, the regenerator unit comprises a compartment that contains liquid desiccant being regenerated and wherein the heat is transferred by the at least one heat pump to liquid desiccant being transported to the compartment. Preferably, the regenerator unit comprises a regenerator sump that receives desiccant after moisture has been removed from it and wherein the heat is transferred to desiccant being transported to the chamber from the regenerator sump.
In a preferred embodiment of the invention, the air conditioner includes a fan to draw air into the cooling unit and wherein the fan is also operative to draw air into the wet air inlet of the drying unit.
In a preferred embodiment of the invention, the air conditioner includes a fan to draw air into the heat exchanger and wherein the fan is also operative to force air exiting the heat exchanger into the hot air inlet of the regenerator.
In a preferred embodiment of the invention, the air conditioner utilizes a refrigerant to which heat is transferred in a condenser in said cooling unit and from which refrigerant heat is transferred in an evaporator in said heat exchanger.
In a preferred embodiment of the invention, the air conditioner cools an interior space and wherein the heat exchanger is outside the space.
Preferably, the wet air inlet communicates to an area outside the controlled area.
In a preferred embodiment of the invention, the controlled area is at least a portion of a building.
In a preferred embodiment of the invention, the proportion of air drawn into the cooling unit via the first and second inlets thereto is at least partially controllable.
There is further provided, in accordance with a preferred embodiment of the invention, a dehumidifier system comprising:
a liquid desiccant in two reservoirs, one of which contains a higher desiccant concentration than the other;
a dehumidifier unit into which moist air is introduced and from which less moist air is removed after dehumidification by liquid desiccant transferred thereto;
a regenerator unit which receives desiccant solution that has absorbed from the moist air and removes moisture from it; and
a passageway connecting the reservoirs, via which passageway, during steady state operation of the dehumidifier, there is a net flow of moisture from the reservoir having the lower desiccant concentration to the other reservoir without there being a net flow of desiccant ions through the passageway.
Preferably, the passageway is an aperture such that the level of liquid desiccant in the two reservoirs is the same.
In a preferred embodiment of the invention, there is no pumping of liquid desiccant from one reservoir to the other. Preferably, the transfer of moisture is by gravity.
In a preferred embodiment of the invention, there is no transfer of liquid desiccant between the reservoirs except via apertures connecting the reservoirs.
In a preferred embodiment of the invention, the two reservoirs include a first reservoir which receives said liquid desiccant from said dehumidifying chamber after said desiccant absorbs moisture thereat. Preferably, liquid desiccant is transferred to the dehumidifying chamber from the first reservoir.
In a preferred embodiment of the invention, the two reservoirs include a second reservoir which receives said liquid desiccant from said regenerator after removal of moisture therefrom. Preferably, liquid desiccant is transferred to the regenerating chamber from said second reservoir.
In a preferred embodiment of the invention, the dehumidifier includes a heat pump that transfers heat from relatively cooler liquid desiccant to relatively warmer liquid desiccant. Preferably, the heat pump pumps heat from the reservoir having the lower concentration of desiccant to that having the higher concentration of desiccant. In a preferred embodiment of the invention, the heat pump transfers heat from desiccant in a conduit carrying desiccant to the dehumidifier unit.
In a preferred embodiment of the invention, a substantial temperature differential is maintained between the first and second reservoirs. Preferably, the temperature differential is at least 5xc2x0 C. In some preferred embodiments of the invention, the temperature differential is at least 10xc2x0 C. or at least 15xc2x0 C.


The present invention is aimed at techniques for detecting the “partial loss” of an upper layer frame. One technique envisions a detection platform adapted to determine whether a packet is a final packet for a particular upper layer frame. A comparator platform then compares packets received free of transmission errors with variables indicative of whether all received packets in the particular upper layer frame have been received correctly when a final packet is detected. A transmission platform then sends a signal indicative of whether the packets received without transmission errors constitute the particular upper layer frame so that lost packets can be retransmitted quickly.

A common function of a data communication system is to successfully send data "packets" containing desired information from a transmission point or node to a reception point or node. Before going further, it should be understood that the term "node" may indicate one or more hardware, software or firmware elements which may be combined or used separately to carry out transmission and/or reception of packets, etc. . . . In order for such a system to perform efficiently, bits of information are grouped together to form an "upper layer frame". Upper layer frames are then further subdivided or concatenated into packets, the basic units used for transmission in a communication network.
A communication network's efficiency is measured by how many packets it can successfully send from a transmission node to a reception node in a given time period. This measurement is known as a network's "throughput". Another measure of network efficiency is the amount of time it takes for a packet to get from a transmission node to a reception node. This performance metric is known as "delay". An ideal communication network will transmit the maximum amount of packets between network nodes in the least amount of time.
Several factors prevent both wire line and wireless communication networks from achieving ideal throughput and delay performance. Principally among them are transmission failures caused by interference, weak transmissions or faulty reception. One known technique used to minimize network transmission failures utilizes an Automatic Repeat Request (ARQ) retransmission method of error correction. ARQ retransmission uses a "reverse acknowledgement" channel. This channel can be a stand-alone channel or multiplexed with a "reverse data channel". A reverse acknowledgement channel allows a reception node to provide a transmission node with the status of transmitted packets. These status messages are aptly called "acknowledgements".
ARQ retransmission is used, for example, in a radio link control protocol developed for third generation, 3G communication networks (3G is short for third generation, 3GPP/UMTS radio link protocol communication networks). These networks support wireless bandwidth requirements for telephone calls, global positioning systems, email, Internet access, videoconferencing and streaming audio and video. Today, 3G networks allow data to be transmitted between a transmission node and reception node over a range of 8 kb/sec to 2 MB/sec. Future enhancements may enable 3G networks to transmit data up to 10 MB/sec. An efficient ARQ retransmission method is essential in order to maintain network protocol integrity for commercial applications, especially when it comes to 3G networks which require high data transfer rates.
Before describing the details of the present invention, it may be helpful to first present a simplified explanation of ARQ retransmission and how it applies to 3G networks.
Referring to FIG. 1, there is depicted a simplified block diagram of a conventional communication network 100 comprising a communications channel 110, an acknowledgement channel 112, a reception node 104 and a transmission node 102. In an existing ARQ retransmission method, the transmission node 102 is adapted to send packets stored in a memory unit 106, which can also be referred to as a transmission buffer, along the communication channel 110 to a reception memory unit 108, which can also be referred to as a reception buffer, for examination. Circuitry in the reception node 104 is adapted to examine the incoming packets in the reception memory unit 108 to determine whether they have been transmitted successfully, as further discussed below. If the reception node 104 receives a packet that contains corrupted data, the reception node 104 circuitry is adapted to send a status or acknowledgement message back to the transmission node 102 on the acknowledgement channel 112. More to the point, the reception node 104 will only be adapted to send an acknowledgement when corrupted data is received. This type of ARQ retransmission method is known in the art as a "negative" acknowledgement (NACK) method.
Alternatively, the reception node 104 may be adapted to send an acknowledgement via the acknowledgement channel 112 to the transmission node 102 only when it is determined that a packet sent via communication channel 110 has been received without errors. This type of ARQ retransmission method is known in the art as a "positive" acknowledgement method. In this method, the transmission node 102 is adapted to wait for a predetermined time period to receive an acknowledgement from the reception node 104. If an acknowledgement is not received within the predetermined time period, the transmission node 102 is adapted to retransmit the unacknowledged packet stored in the memory unit 106 to the reception node 104.
It is known in the art that positive and negative ARQ retransmission methods can be combined into a "general" ARQ retransmission method where acknowledgements are sent from a reception node to a transmission node on an acknowledgement channel for every previously transmitted packet in the memory unit. Based on the received acknowledgements, the transmission node will be adapted to determine whether a given previously transmitted packet stored in the memory unit needs to be retransmitted to the reception node. Generally, the transmission node is adapted to wait until it receives an acknowledgement before it makes any decision on whether to continue to hold previously transmitted packets in the memory unit or to clear the unit for the next incoming stream of packets.
As mentioned above, a specific use of a general ARQ retransmission method is in 3G networks. Within a so-called "protocol stack" of a 3G network, a radio link control (RLC) layer contains protocols (e.g., a series of set instructions) used to carry out ARQ retransmission. FIG. 2 is a simplified block diagram illustrating components of an RLC layer 200 relevant to our discussion. As shown, layer 200 comprises a transmission unit 202 and reception unit 210.
The path of a packet can be traced through the RLC layer 200. Upper layer(s) 102u send upper layer frames to the transmission unit 202 which is adapted to process such frames as follows. Before the upper layer frames can be transmitted, segmenting unit 204 is adapted to segment and/or concatenate them into packets. Thereafter, an RLC header unit 206 is adapted to add an RLC header to each packet. Packets are then placed in the memory unit 106 to wait for transmission. (Note that the memory unit may function as either a transmission or retransmission buffer and that these elements may be implemented either by one or more devices, platforms, programs or the like or separate devices). A multiplexer circuit 208 is adapted to select which packets from memory unit 106 will be transmitted during a next "transmission time interval" (TTI) and to calculate when the selected packets will be submitted to a lower layer 102l for actual transmission. If the memory unit 106 is implemented using separate transmission and retransmission elements, the selected packets can come from the transmission buffer element, retransmission buffer element or both.
A Medium Access Control ("MAC") layer (not shown) determines the number of packets which can be transmitted per TTI and sends this information to RLC Layer 200 via pathway 300. Header unit 206 is then further adapted to set certain fields, which may represent a variety of protocol variables, within each packet selected for transmission.
Subsequently, selected packets are transmitted via transmission lower layer section 102l to reception lower layer 104l.
The reception section 210 is adapted to receive transmitted packets from the reception lower layer 104l. An expansion unit 212 is adapted to expand the received packets into separate packets and to place them in a reception memory unit 108 until packets associated with an entire reconstructed upper layer frame have been received.
At this point, the reception section 210 is adapted to generate and send acknowledgements and status information on individual packets stored in the reception memory unit 108 to the transmission section 202 as follows. A transceiving unit 214 is adapted to analyze whether the packets within the reception memory unit 108 have been received without errors. The unit 214 is further adapted to send this information to a transmission unit 216 via reverse link 112. (A separate element, such as a reception node transmission unit, may also be adapted to send this information.)
Unit 216 is adapted to control the multiplexer circuit 208 in order to select packets for transmission during the next TTI. When packets are successfully received and acknowledged, a reception header unit 218 is adapted to remove the RLC header from each packet, reassemble the frame and to send the reassembled frame to upper layer 104u.
It is generally believed that frequent acknowledgements allow retransmissions to be carried out quickly, which benefits delay performance and overall system efficiency. In addition, frequent acknowledgements allow a memory unit (transmission buffer) to be cleared more frequently. This reduces the likelihood that the memory unit will overflow. Furthermore, frequent acknowledgements can prevent instances of protocol stalling, which occurs when a transmission node is unable to transmit packets even though there are packets available for transmission in its memory unit.
On the other hand, frequent acknowledgements consume the bandwidth of a reverse link, degrade the throughput and delay performance of the reverse link and interfere with other transmissions.
For these and a variety of reasons, current acknowledgement techniques are inefficient. To be efficient, a communication network, including a 3G network, must make efficient use of its limited bandwidth to send the most amount of information in the least amount of time. While, as discussed above, existing acknowledgement techniques generally facilitate faster communications, these techniques must also be utilized efficiently or their benefit to a system's performance will be lost. Therefore, it is unacceptable to allow an uncontrolled volume of acknowledgement signals to be sent to a transmission node.
There is a particular need in the art of wireless and wire line communication network protocols, especially RLC layer acknowledgement protocols utilized in 3G communication networks, for acknowledgment techniques that balance the need to retransmit negatively or unacknowledged packets with the need to maintain overall network efficiency. Further, retransmission must be managed so that error correction can be invoked as fast as possible, but is utilized conservatively to prevent excessive delays and protocol stalling.
There is also a need in the art for techniques adaptable to rectify transmission errors occurring in 3G and other communication networks that improve the throughput of the network and reduce delays relative to current retransmission schemes. For data communication, where the integrity of the upper layer frames is essential to reliable service, such techniques should also be able to detect whether the transmission time of an upper layer frame has been prolonged, and appropriately retransmit associated packets to reduce the packet delay for the upper layer frame.
Finally, there is a need in the art for data packet retransmission techniques that incorporate the performance enhancing characteristics described above and are general enough to be incorporated into a variety of data communication networks, not just 3G communication networks.

Methods and devices for partial upper layer frame loss detection based retransmission


This semiconductor circuit includes a plurality of memory cell arrays arranged mutually adjacent in one direction, a plurality of first selection/sense amplifier circuits provided in the respective regions between mutually adjacent pairs of these memory cell arrays and make access to one of alternately defined odd-numbered or even-numbered memory cell trains in the order of arrangement, two units of second selection/sense amplifier circuits arranged on the outside of the memory cell arrays on both ends of the arrangement of the plurality of memory cell arrays and make access to one of the designated odd-numbered or even-numbered memory cell trains of the memory cell arrays on both ends, a plurality of data buses corresponding to the respective bits of data transferred in bit parallel between an external circuit, and a plurality of input and output switching circuits arranged and connected in one-to-one correspondence to the respective first and second selection/sense amplifier circuits connected to the plurality of data buses so as to have an equal number of memory cell trains capable of transferring data with these data buses, and a plurality of input and output switching circuits which transfer data with the first and the second selection/sense amplifier circuits in one-to-one correspondence.

1. Field of the Invention
This invention relates to a semiconductor memory circuit, and more particularly to a semiconductor memory circuit which includes shared sense amplifiers and is adapted for multibit parallel input and output configuration and for increasing the capacity.
2. Description of the Prior Art
In semiconductor memory circuit, the folded bit line structure in which a bit line for giving a reference potential to a sense amplifier (referred to as bit line for reference potential hereinafter) and a bit line for reading out data of a memory cell (referred to as bit line for read hereinafter) are arranged on one side of the sense amplifier, gives less induced noise to the bit line compared with the open bit line structure which the bit line for reference potential and the bit line for read are arranged on the mutually opposite sides of the sense amplifier, so that it is currently in widespread use for semiconductor memory circuits.
Moreover, since in a semiconductor memory circuit such as a dynamic RAM (referred to as DRAM hereinafter) the ratio of the capacity of the memory cell capacitor (referred to as capacity of memory capacitor hereinafter) to the parasitic capacity of the bit line (referred to as capacity of bit line hereinafter) is related directly to the read voltage generated in the bit line, this ratio is an important parameter for the design of DRAM. The capacity of bit line is determined by the number, the size, and the structure of memory cells connected to the bit line, and the structure, size, material, or the like of the bit line itself. Accompanying the advancement of the generation of semiconductor memory circuits and the increase of the memory capacity, geometrical refinement or the memory cell and the bit line is advanced and the capacity of bit line is decreased. On the other hand, it brings about a decrease of the capacity of memory capacitor and an increase of the induced noise, and the number of the memory cells connected to one bit line has not been changed since it was increased from 64 bits to 128 bits for 256 kbit DRAM, even for the advances of the memory capacity of 1M bits, 4M bits, and 16M bits. Various kinds of split bit line modes have been proposed in order to keep the number of memory cells connected to one bit line constant, in the midst of the alternation of generation of DRAM as mentioned above, under the condition of limited chip size. Among them, the multisplit bit line shared sense amplifier mode (referred to as shared sense amplifier mode hereinafter) is being adopted most widely for the reasons is that it is possible to realize a reduction of power consumption and an improvement of operating speed, and is most advantageous from the viewpoint of chip size (see for example, 16Mbit DRAM .mu.PD4216400 made by NEC Corporation which is the assigned of this application).
Next, an example of semiconductor-memory circuit of the shared sense amplifier mode will be described.
This semiconductor memory circuit comprises a plurality of memory cell arrays each including a plurality of memory cell trains connected respectively to bit line pairs of folded bit line mode, and are arranged in the direction in which each of these memory cell train extends while keeping the mutual correspondence relation among these memory cell trains, a plurality of first selection/sense amplifier circuits each including first selection means which is arranged in every interarray regions between the pair of mutually adjacent memory cell arrays and selects for each member of the respective pairs either of an odd-numbered train or an even-numbered train of the plurality of memory cell trains of the memory cell arrays on both sides of the interarray region, a plurality of sense amplifiers which amplify the respective read data of the memory cell trains selected by the first selection means in one-to-one basis, and second selection means which selects one of the plurality of sense amplifiers and one of the memory cell trains selected by the first selection means and connect them to the corresponding data input and output lines, and transmits one of the amplified read data of an odd-numbered or an even-numbered memory cell train of the selected memory cell array on one side to the corresponding data input and output lines and supplies write data transmitted to the corresponding data input and output lines to a selected memory cell train of a selected memory cell array, two units of second selection/sense amplifier circuits each including a plurality of sense amplifiers arranged on the outside of the respective memory cell arrays at both ends of the disposition of the plurality of memory cell arrays and amplify in one-to-one basis read data of memory cell trains set differently from those of the first selection/sense amplifier circuits corresponding to the outermost memory cell arrays and selection means which selects one of the plurality of the sense amplifiers and one of the set memory cell trains of the outermost memory cell array and connects them to corresponding data input and output lines, and transmit amplified read data from the set memory cell trains of the outermost memory cell arrays to corresponding data input and output lines and supply write data transmitted to the corresponding data input and output lines to selected memory cell trains of the outermost memory cell arrays, a plurality of data buses corresponding to the respective bits of data which is transferred in bit parallel mode between an external circuit, and a plurality of input and output switching circuits which transmit the respective read data from the memory cell arrays one by one to the corresponding data buses via the first and the second selection/sense amplifier circuits by sequentially assigning equal number of memory cell arrays in the order of arrangement to the plurality of data buses, respectively, and apply write data transmitted to these data buses from the external circuit to respective selected memory cell trains of the corresponding memory cell arrays.
If it is assumed in this semiconductor memory circuit that, for example, the number of the memory cell arrays is eight, the number of the data buses is four, and the data transfer between the external circuit is carried out in four bit parallel mode, then seven first selection/sense amplifier circuits are arranged among eight memory cell arrays, a second selection/sense amplifier circuit is arranged on the outside of the each of the outermost memory cell array of the eight memory cell arrays, and a plurality of input and output switching circuit are arranged between the first and second selection/sense amplifier circuits and four data buses. Since two memory cell arrays each are made to correspond sequentially in the order of arrangement to the respective members of the four data buses, the first and the second memory cell arrays from the left correspond to the first data bus, the third and the fourth memory cell arrays correspond to the second data bus, the fifth and the sixth memory cell arrays correspond to the third data bus, and the seventh and the eighth memory cell arrays correspond to the fourth data bus. Further, if the first and the second selection/sense amplifier circuits are designated from the left as the first, the second, . . . , and the ninth sense amplifiers, the data transmission between the first and the second memory cell arrays and the first data bus is executed via the first, second, and the third selection/sense amplifier circuits, the data transmission between the third and the fourth memory cell arrays and the second data bus is executed via the third, the fourth, and the fifth selection/sense amplifier circuits, and similarly, the data transmission between the fifth and the sixth memory cell arrays and the third data bus is executed via the fifth, the sixth, and the seventh selection/sense amplifier circuits, and the data transmission between the seventh and the eighth memory cell arrays and the fourth data bus is executed via the seventh, the eighth and the ninth selection/sense amplifier circuits.
As in the above, in this semiconductor memory circuit, the third, the fifth, and the seventh selection/sense amplifier circuits have to carry out the data transfer between the respective two data buses. For this reason, it becomes necessary to have two input and output switching circuits between these selection/sense amplifier circuits and the data buses, and the layout becomes complicated and the chip area needs be increased accordingly.


An improved stereoscopic display apparatus and methodology includes an array of OLED-based pixels that are cleared (i.e., placed in a “dark” state) before being loaded with the desired analog voltage potential signal for display during both left perspective image display periods and right perspective image display periods. In this manner, cross-frame image interference between the left and right perspective images is avoided and the quality of the stereoscopic viewing experience is improved. In another aspect, an improved stereoscopic display apparatus and methodology includes an array of OLED-based pixels. During right perspective image display periods, the pixels of the array are loaded with analog voltage potential signals corresponding to a left perspective image while displaying the preceding right perspective image. Likewise, during left perspective image display periods, the pixels of the array are loaded with analog voltage potential signals corresponding to a right perspective image while displaying the preceding left perspective image. In this manner, cross-frame image interference is avoided and the left and right perspective image display periods can be expanded.

1. Field of the Invention
This invention relates to stereoscopic display methodologies and systems. More particularly, this invention relates to page flipping stereoscopic display methodologies and systems as well as apparatus used therein.
2. State of the Art
Stereoscopic display systems display two perspective images in such a way that each eye of the observer sees only one of the two images. There are many systems in existence that provide this capability through various methods. One of these methods in commonly referred to as "page flipping" or frame-sequential stereo video. In such methods, left and right perspective images are time-division multiplexed and thus displayed during different display periods (i.e., left and right perspective image display periods). Stereoscopic glasses (e.g., shutter-type or polarization-type glasses) are used to ensure that the left perspective images are presented to the left eye during the left perspective image display periods and that the right perspective images are presented to the right eye during the right perspective image display periods.
Autostereoscopic systems have been developed that utilize optics (e.g., lenticular systems, parallax barrier, mirror systems, etc.) to present the left perspective images to the left eye and the right perspective images to the right eye without the need for glasses. Such systems are costly and suffer from various technical problems such as limited depth of field, low brightness, and constrained view regions (i.e., the observer(s) are required to be located in limited viewing area(s) relative to the display).
Emagin Corp. of Hopewell Junction, NY has developed a stereoscopic display system that employs two microdisplays. Each microdisplay emits light from pixels that employs organic light emitting diodes (OLEDs). Such OLED-based microdisplays are advantageous in that they provide good resolution, high contrast ratio, and sufficient brightness for near-eye applications. They are also compactness and lightweight, provide for emissive display such that no backlight or other external light source is required, and also consume less power than displays that employ external light sources. Disadvantageously, the EMagin system employs two OLED-based pixel arrays that are supported near the eyes. One of the OLED-based pixel arrays provides image formation for the left eye, while the other OLED-based pixel array provides image formation for the right eye. Because it uses two separate OLED-based pixel arrays and associated drive circuitry, the EMagin display system is costly.
Page flipping stereoscopic display systems are typically realized with a cathode ray tube (CRT) display that is adapted to operate in a progressive scan mode that alternately displays a left perspective image and a right perspective image. Such systems provide adequate performance but are limited by their screen size, weight and power consumption. With this in mind, users have attempted to employ the prior art page flipping stereoscopic display methodologies to active-matrix liquid-crystal display (LCD) panels. Such panels advantageously provide for increased screen size and significant reductions in weight. However, the backlights (or other external light sources used by such LCD panels) have limited power efficiency. Moreover, when used for page flipping stereoscopic viewing, the line-based update mechanisms employed by LCD panels cause significant cross-frame image interference where the pixels from a left perspective image are displayed concurrently with pixels from a right perspective image as shown in FIG. 1. Such interference degrades the image quality and limits the commercial acceptability of page-flipping LCD-based stereoscopic display systems. LCD-based system. These limitations are also applicable to page-flipping OLED-based stereoscopic display systems.

This patent is subject to a terminal disclaimer.

Method and apparatus for stereoscopic display employing an array of pixels each employing an organic light emitting diode


A bushing and hub assembly are clamped together and clamped on a shaft by passing screws through an annular flange provided on the hub and into threaded openings in the bushing. The outside of the bushing is tapered and the inside bore of the hub has a taper which mates with the tapered outside of the bushing.

1. Field of the Invention
This invention relates to industrial power transmission apparatus. More particularly, this invention is a new bushing and hub structure which is mountable upon a shaft and can easily be removed from the shaft.
2. Description of the Prior Art
A currently manufactured bushing and hub is described in U.S. Pat. No. 2,269,821 dated Jan. 13, 1942 issued to W. W. Kemphert et al. and entitled "SHEAVE." The bushing described in Kemphert et al. includes a bushing with an integral flange. The bushing is tapered on the outside diameter and contains a concentric, cylindrical bore. The integral flange is located at the largest outside diameter of the taper. The flange contains a number of cap screw holes which are used to pull the bushing into a mating hub. The entire bushing is sawed through or split on one side so the bushing will close in on a shaft and clamp to it as the bushing is pulled into the mating taper of the hub.
Newer drive systems using more compact components than previously used often do not afford enough space for the use of a flanged type bushing such as shown in the Kemphert et al. U.S. Pat. No. 2,269,821. These same drives transmit relatively high torques. Therefore, any more compact hub and bushing than the bushing and hub described in the Kemphert et al. patent must not only be compact enough to fit into the newer drive systems of today, but must also be capable of transmitting relatively high torques.
A bushing and hub arrangement which is more compact than the bushing and hub arrangement of Kemphert et al. is described in U.S. Pat. No. 2,402,743 dated Jun. 25, 1946 issued to Firth and entitled "MOUNTING FOR SHEAVES, ETC." Since the Firth structure has no flange, the bushing is pulled into place using several set screws and threaded holes which are located half in the bushing and half in the hub. However, even though the set screw itself acts as a shear bearing member between the bushing and the hub, the forces pulling the bushing into the mating hub and the clamping forces on the shaft are very limited. The forces are limited because neither the threads in the bushing nor the threads in the hub have a full circumference of threads around the set screws.
For newer drive systems a split tapered bushing system which is more compact than the currently manufactured Kemphert et al. hub and bushing but still has the same force magnitude as the Kemphert et al. type hub and bushing to withstand the relatively high torques transmitted by the newer drive systems would obviously be highly desirable.
My invention is a new split tapered bushing system for use in power transmission systems which is more compact than the currently manufactured flanged bushings of the type shown in the Kemphert et al patent and yet provides sufficient clamping ability to be used with the newer drive systems which transmit relatively high torques.

Shaft mountable bushing and hub for industrial power transmissions


It is disclosed an amusement device (1) comprising a vehicle (2) riding on a track (3), said vehicle comprising a support frame (4) and a compartment (5) having one or more seats (52) for housing one or more passengers, the compartment being moveably connected to said support frame by a shaft (7), to rotate about an axis (Y) with respect to said support frame, from a first position (P1) to at least one second position (P2) in a rotation angular interval, at least when a centrifugal force acts on the passenger compartment (5). The vehicle comprises at least one restoring element (6) configured to rotate back said compartment (5) towards said first position (P1) for at least part of the angular interval between said at least one second position (P2) and said at least one first position (P1). The restoring element (6) is directly or indirectly constrained to said shaft (7).

For example, US2003172834 by the applicant DE-GOL GINO et alii, describes a moving apparatus having a platform provided with a conventional industrial robot, particularly a robot with six inherent moving axes, with base, rocker, robot arm and robot hand carrying a passenger carrier provided with a frame and two seats. The robot is able to move in a controlled way the base, the rocker, the robot arm and the robot hand in order to move the passenger carrier in any direction of the space during the riding of the platform on the track.
This type of moving apparatus is extremely complex from a constructional point of view because of the presence of the robot and the fact that a personal computer has to be mounted onboard the platform to control the movements of the robot's components. Alternatively, an antenna has to be mounted on the platform to receive an external signal that controls the movements of the robot's components. Furthermore, the robot controls any movement of the passenger carrier, in particular during the turns along the track, thus making the experience for the passengers in some ways "piloted".
WO03/082421, discloses a similar amusement ride wherein a vehicle is movable along a track. The vehicle can be rotated about different rotation axes. The rotation is controlled by actuators such as electric motors, or pneumatic systems, thus limiting the experience for the passengers that is also in this case "piloted".
The European patent EP2175951B1, in the name of Vekoma Rides, discloses a roller coaster for simulating a racing position on a motorbike. The passenger assembly includes a frame that is connected to a carriage and that is provided with a chest support, a back restraining member, and a leg restraining device for each leg. Additionally, the frame of the passenger assembly, and in particular the suspension arm, is suspended from the carriage by means of a pivot. The pivot axis is substantially directed longitudinally, i.e. substantially parallel with respect to the advance direction of passenger assembly along the roller coaster track. The passenger assembly will swing in pendulum fashion on a vertical plane as the carriage passes through a turn, that is to say when the frame is subjected to a centrifugal force. The above mentioned pendulum swing is damped by means of two dampers arranged laterally to the suspension arm. When the centrifugal force no longer acts on the frame, that is to say when the carriage passes through a straight path, the frame returns to its initial vertical position being subjected to the gravitational force.
EP0115355 discloses a similar ride provided with a suspended carriage. The suspension is achieved by two support rods connected to each other by means of a shaft, extending along the movement direction of the ride. The suspended carriage can be rotated about the axis defined by the carriage movement direction.
Also in this case, the oscillating movement of the suspended carriage is damped by pneumatic or hydraulic damping cylinders,
However, this last type of amusement rides are not without drawbacks. In fact, suspension arm could remain blocked in a tilted position in case the centrifugal force to which the suspension arm is subjected is excessively high, with consequent hazards for the passengers. Additionally, because the vehicles are suspended from the track, the track with the rail is thus necessarily located above the vehicles, this being a disadvantage in that the view of the passengers is obstructed by the rail. Another problem is that the vehicle is hanging in a plane substantially perpendicular to the plane of the rails.
Therefore, there is the need to increase the safety of this kind of amusement devices, while at the same time giving to the passengers an open free experience, not piloted by direct or active control.
It is also known from document WO2015/040195, in the name of the present Applicant, an amusement device wherein a passenger compartment is constrained to an arm that is rotatable about a pivot when the centrifugal force acts on the compartment. The compartment rotates in a plane that is substantially parallel to the plane of the rails. Restoring means are arranged to restore the arm in a first position when the centrifugal force no longer acts on the arm.
In the amusement device disclosed in WO2015/040195 the arm, and the compartment for the passenger, can be restored to the initial position by restoring means, preferably of the passive type. The movement of the arm is not caused by an actuator, or similar actuation means, and is therefore not piloted by any direct, or active, control; the restoring means need thus to cooperate with the arm. More in detail, the restoring means comprise a ramp and at least one variable-length leg sliding along said at least one ramp when a centrifugal force acts on the arm.
An object of the present invention is also to provide an amusement device wherein the experience of the passengers can be increased by giving them an open free experience, not piloted by any direct or active control on the moving arm and the passenger carrier, while providing an effective way of restoring the passengers' compartment in the first, i.e. initial, position.
An object of the present invention is to provide a way to restore the passenger compartment in the first position that is simple to realize and quick and effective in use. The compartment should rotate in a plane that is substantially parallel to the plane of the rails.
Another object of the present invention is to provide an amusement device wherein the restoring means are simple and effective and can provide an effective restoring force in both directions of rotation (clockwise and counterclockwise).


Embodiments of the present invention provide moisture measuring systems and methods. According to one embodiment of the present invention, a sealable compartment is used in which a specimen containing liquid can be inserted, such that all of the specimen is contained within the compartment. The relative humidity in the compartment is measured over a duration of time, which can be used to calculate the amount of liquid leaked by the specimen. Embodiments of the present invention can be utilized, for example, to calculate the leakage rate of water-carrying hardware of a cooling system, without having to create a membrane or other isolated sample of materials.

The present invention relates generally to the field of moisture leakage, and more particularly to measuring moisture leakage through water-carrying hardware.
Computer processor speeds have increased in recent years. Typically, air moved by fans is used to cool these computer processors. With the increase of computer processor speeds, the heat produced by processors has also increased along with the noise generated by the equipment (e.g., fans) used to cool those processors. Water cooling, as applied to computers, refers to a method used to lower temperatures of computer processors using water rather than air as the cooling medium. Because water can conduct heat about 30 times faster than air, water cooling can allow computer processors to run at higher speeds and reduce noise produced by cooling equipment.
The ability of water cooling hardware systems to cool computer hardware can be diminished, or even lost, as water permeates through, or leaks past, various materials and/or connections of materials. Determining a rate of loss of coolant from the cooling system can help designers of these water cooling hardware systems determine maintenance procedures for these systems.

Measuring moisture leakage through liquid-carrying hardware

International Business Machines Corporation


The dental device comprises an elongated inflatable balloon for placement around a matrix band in part surrounding relationship with a decayed tooth. Upon inflation, the balloon evenly applies the matrix band against the tooth.

This application is based upon European Patent Application No. 97103023.4 filed in the European Patent Office on Feb. 25, 1997, the priority of which is hereby claimed under 35 U.S.C. .sctn. 119. This invention relates to a dental medicine device for pressing a wall molding means against a decayed tooth for restoration thereof, comprising expandable means for urging said wall molding means against the decayed tooth wall to hold restorative material inserted into the tooth.
Dental restoration of cavities between teeth is common practice in dentistry. When it is necessary to restore the portion of a tooth which, prior to decay, contacted an adjacent tooth, it is indispensable to confine the restoration material during placement and until rigid enough, to support itself to conform exactly to the healthy portion of the tooth. Any surplus or overhang of restorative material in the hardly reachable approximal areas constitutes an irritation source which leads to plaque accumulation and constitutes enormous niches for the cariogenic flora. With time, the initially gram-positive flora transforms into parodontopathogenic gram-negative flora which leads to acute and/or chronic periodontal disease.
In order to position the restorative material, it is customary to fit, by means of an appropriate tensioner also called retainer or holder, a matrix band around the tooth for creating a mold to replace the wall lost by caries and cavity preparation during insertion of the restorative material into the tooth. To achieve its function, the matrix band must be fixed in position, and it must be formed as close as possible to the shape of the tooth so that the restorative material placed therein will conform to the outer surface of the healthy portion of the tooth. However, because of the convexity or concavity of the tooth at the site of restoration, the matrix band tends to stand away from the tooth, thereby allowing surplus or overhang of the restoration material to pass between the tooth and the matrix band. This is especially the case when bonding agents and/or flowable composite materials are used to restore the tooth.
Accordingly, a wedging of the matrix band is made, by means of a wedge which is forced between the adjacent teeth in the region between the former contact point and the gingiva to press the matrix band material against the tooth at the floor of the cavity preparation. The wedge is also aiming to perform an additional function in that it forces the teeth apart creating a wider space therebetween than would normally exist. This is important because the matrix band occupies an amount of space which would persist when the matrix band is removed if the elastic memory of the periodental membrane would not move the teeth closer together after removal of the wedge which caused the temporary separation.
Typical wedging technique provides for tapered elongated wooden wedges which may be inserted between adjacent teeth with friction being relied upon to maintain the wedge in position. Since the interdental papilla occupies the approximal space between the teeth, insertion of the wedge causes an injury inducing rubbing compression to the tissue between the teeth. Furthermore, the wedge tends to slip out of position due to the poor frictional engagement provided. As the material forming the wedge is only slightly deformable with practically no elastic memory, all the force applied for placement of the wedge is transmitted to the attachment of the teeth to the bone, with the risk of trauma at this level, whereby the force created by the wedge can be lost. And, most of all, as the tooth contour is quite variable at the site of restoration, with discontinuities and convexities, respectively concavities bordered with convexities, wedge cannot provide more than tangential or point contact between the wedge, the matrix band and the tooth. There is therefore significant pressure on the matrix band area where convexity of the tooth is most pronounced; other areas of the matrix band get only mild pressure or no pressure at all. The result is a loose fit of the matrix band to the tooth, with unavoidable surplus or overhangs of restorative material between the tooth and the matrix band. Of course, it is possible to try to tailor the wedge in an attempt to provide a better fit between wedge, matrix band and tooth; however, this is time consuming and the result is quite aleatory because of difficult to ascertain parameters such as the complex geometry of the tooth and the advance of the wedge between the teeth to assume the required friction fit and pressure of the wedge on the matrix band and tooth.
Where composite resin restorations for light curing technique are used, light transmitting plastic wedges have been developed to transfer light energy for curing of the restorative material. The problems outlined hereabove remain however unsolved, with the added risk that surplus and overhangs of the restorative material may result in leaks in the restorative material which may induce cracks or hollow spaces in the material, thereby reducing its efficiency and creating further niches for the pathogenic flora.
There has been various attempts to provide better wedging. For example, U.S. Pat. No. 3,890,714 shows a plastic wedge with a dihedral body the lateral walls of which are flexible and slotted to increase the friction coefficient between the wedge and adjacent elements; although possibly reducing the risk of trauma at attachment level of the teeth and raising the friction anchor between the teeth, this wedge still cannot solve the problem of a loose matrix band fit; in addition, this wedge has a tendency to lacerate the gingival tissue.
U.S. Pat. No. 3,815,243 discloses a trihedral wedge of soft plastic material with serrations defined by transverse protrusions intended to more evenly distribute the pressure; although outlining the problem of poor matrix band application resulting in surplus of restorative material between the tooth and the matrix band, this wedge still cannot solve that problem because the serrations cannot evenly match the discontinuities, convexities, and concavities of the tooth contour at the site of restoration.
U.S. Pat. No. 4,337,041 refers to a wedge the elongated body of which is provided with depressions intended to positively engage the teeth and simulate the contour of the concave interdental papilla. The wedge is thus preshaped and it can consequently not match the tooth shapes which are different in each case of restoration. The problem of uneven pressure for the matrix band is thus unsolved. In addition, the edges of the depression simulating the contact of the interdental papilla may lacerate the tissue upon insertion of the wedge.
U.S. Pat. No. 5,573,400 describes an expanding dental wedge having a trihedral elongated tapered body. Other cross-sectioned shapes such as trapezoidal or round are possible. This wedge is made of compressed hydrophilic material, such as cellulose or synthetic foams, that expand in contact with moisture. Accordingly, after placement of the matrix band, the wedge is inserted conventionally into the interproximal area between teeth. At this stage, addition of moisture is required to begin an expansion process. The moisture may be applied by the practitioner in the form of water and moisture from the interproximal tissues is said to also enter into matter for the expansion process. The document indicates that the moisture causes a pronounced expansion of the compressed material, providing reciprocal pressure to all points of the matrix band along the proximal surface, thus providing a matrix band seal. The document also indicates that the wedge is more gentle to interdental tissues due to its pliable nature when in contact with moisture. Although this technology may appear appealing, there are serious drawbacks. The expansion and pressure which may result therefrom are totally uncontrollable. The rate of expansion with respect to the amount of moisture is unknown; it is not only bound to the moisture applied by the practitioner, it also depends from variations of the moisture conditions of the gingival tissue and bucal environment, and it further varies as a function of the homogeneity of the compressed material along the length of the wedge. The practitioner has absolutely no means to know how the pressure resulting from the expansion will distribute. The pressure resulting from the expansion may be too low to properly apply the matrix band to sharp convexities or concavities or irregularities of the tooth contour, whereby the risk of poor or loose positioning of the matrix band against the tooth, and the added risk of insufficient force to take the teeth apart from one another. If the pressure is too high than would be required for proper application of the matrix band to the tooth contour there is the added risk of trauma for the teeth attachment. Once the moisture expansion initiated, there is no way to stop or to reduce it otherwise than by a difficult if not impossible drying procedure, whereby the practitioner cannot change the matrix band positioning if he deems it advisable to do so before the restorative material filling procedure. The system therefore cannot be failproof to avoid the risk of surplus or overhangs of restorative material between the tooth and matrix band and the risk of trauma. Apart of this, the document is silent as to how the expanded wedge may be withdrawn from the interdental papilla; forcible withdrawal of the expanded wedge may cause injury to the interdental papilla as well as it may cause an overspacing of the teeth from one another and consequent trauma. Furthermore, rubbing insertion of the compressed dried material may also cause injury to the interdental papilla. And the compressed expandable material forming the wedge does not appear to be appropriate for the transmission of light energy as required for curing plastic or composite restorative materials. Moreover, the wedge is contraproductive since successful handling of filling materials requires 100% dryness. Moisture reduces the quality of restorations. Thus a rubber dam is to be applied to keep the operated area dry.
All references cited herein, including the foregoing, are incorporated herein in their entireties for all purposes.


An aspect of the present disclosure relates to a chemical mechanical planarization pad including a first domain and a second continuous domain wherein the first domain includes discrete elements regularly spaced within the second continuous domain. The pad may be formed by forming a plurality of openings for a first domain within a second continuous domain of the pad, wherein the openings are regularly spaced within the second domain, and forming the first domain within the plurality of openings in second continuous domain. In addition, the pad may be used in polishing a substrate with a polishing slurry.

Chemical-mechanical planarization may be understood as a process whereby a wafer or another substrate is polished to achieve a relatively high degree of planarity. The wafer may be moved relative to the chemical-mechanical planarization (CMP) pad in close proximity to each other, under pressure, and/or with a continuous or intermittent flow of abrasive containing slurry applied between them. A conditioner disk having a surface comprising relatively hard abrasive (typically diamond) particles may be used to abrade the pad surface to maintain the same pad surface roughness for consistent polish. In semiconductor wafer polishing, the advent of relatively large scale integration (VLSI) and ultra large scale integration (ULSI) circuits has resulted in the packing of many more devices in relatively smaller areas in a semiconductor substrate, necessitating greater degrees of planarity for the higher resolution lithographic processes that may be required to enable the dense packing. In addition, as copper and other relatively soft metal, metal alloys or ceramics are increasingly being used as interconnects due to relatively low resistance and/or other properties, the ability of the CMP pad to yield relatively high planarity of polish without causing scratching defects may become critical for the production of advanced semiconductors. Relatively high planarity of polish may require a relatively hard and/or rigid pad surface to reduce local compliance to the substrate surface being polished. However, a relatively hard and/or rigid pad surface may tend to also cause scratching defects on the same substrate surface thus reducing production yield of the substrate being polished.

Chemical-mechanical planarization pad including patterned structural domains


A plasma display device is provided. The plasma display device includes a plasma display panel (PDP) and an external light shield sheet which absorbs external light incident upon the PDP. The external light shield sheet includes a base unit and a plurality of pattern units which are formed in the base unit. Each of the pattern units contains 2-10 weight % of light absorption particles having a size of 1 μm or less. Since the external light shield sheet which can absorb and shield as much external light as possible is disposed at the front of the PDP, the plasma display device can effectively realize black images and improve bright room contrast.

1. Field of the Invention
The present invention relates to a plasma display device, and more particularly, to a plasma display device in which an external light shield sheet for shielding external light incident upon a plasma display panel (PDP) is disposed at a front of the PDP so that the bright room contrast of the PDP can be improved, and that the luminance of the PDP can be uniformly maintained.
2. Description of the Related Art
In general, plasma display panels (PDPs) display images including text and graphic images by applying a predetermined voltage to a number of electrodes installed in a discharge space to cause a gas discharge and then exciting phosphors with the aid of plasma that is generated as a result of the gas discharge. PDPs are easy to manufacture as large-dimension, light, and thin flat displays. In addition, PDPs can provide wide vertical and horizontal viewing angles, full colors and high luminance.
In the meantime, external light incident upon a PDP may be reflected by an entire surface of the PDP due to white phosphors that are exposed on a lower substrate of the PDP. For this reason, PDPs may mistakenly recognize and realize black images as being brighter than they actually are, thereby causing contrast degradation.

External light shield sheet and plasma display device using the same


The present disclosure relates to a pulse cleaner for cleaning a diesel exhaust treatment device. The pulse cleaner includes a cabinet, a diesel exhaust treatment device mount positioned within the cabinet for mounting the diesel exhaust treatment device during pulse cleaning, and a collection filter positioned within the cabinet for collecting material displaced from the diesel exhaust treatment device during cleaning. The pulse cleaner also includes a pulse generator for generating pulses that are each directed at a majority of a face of the diesel exhaust treatment device when the diesel exhaust treatment device is mounted at the diesel exhaust treatment device mount. The pulse generator includes a pressure tank for accumulating pressurized air, and a valve arrangement that flushes the pressurized air from the tank. A pulse of air for cleaning the diesel exhaust treatment device is generated each time the tank is flushed.

To reduce air pollution, engine exhaust emissions standards have become increasingly more stringent. After treatment devices have been developed to satisfy these increasingly stringent standards. For example, catalytic converters have been used to reduce the concentration of pollutant gases (e.g., hydrocarbons, carbon monoxide, nitric oxide, etc.) exhausted by engines. With respect to diesel engines, diesel particulate filters have been used to reduce the concentration of particulate matter (e.g., soot) in the exhaust stream. U.S. Pat. No. 4,851,015, which is hereby incorporated by reference, discloses an example diesel particulate filter. Other example types of after treatment devices include lean NOx catalyst devices, selective catalytic reduction (SCR) catalyst devices, lean NOx traps, or other device for removing for removing pollutants from engine exhaust streams.
At times, it is required to service after treatment devices. To facilitate servicing, after treatment devices are often clamped into an exhaust system as modules or separate units. For example, clamps can be provided at flange interfaces located opposite adjacent opposite ends of the after treatment devices. By removing the end clamps, a given after treatment device can be removed from its corresponding exhaust system for servicing.
In use, after treatment devices occasionally become overloaded with soot, ash or other materials present in or generated from engine exhaust. As after treatment devices become overloaded, the devices cause undesirable backpressure in their corresponding exhaust systems. Before an after treatment device becomes plugged to the point where excessive backpressure is a concern, it is recommended to remove the device from its corresponding exhaust system for servicing. To service a device such as a diesel particulate filter, it is known to manually move a focused stream of pressurized air back and forth across the outlet side of the filter to loosen soot/ash that has collected on the filter. For example, a dry air gun (e.g., 50-100 psi) can be used as a source of pressurized air. Simultaneously, an industrial vacuum device is coupled to the inlet side of the filter. The vacuum device is typically equipped with a high-efficiency particulate air filter or ultra-low penetration air filter for collecting the soot/ash that is blown from the filter by the pressurized air. Total time for cleaning the filter depends on the size of the filter, but is typically 30-50 minutes.
Pulse cleaners have been used in other filtration applications to clean filters. For example, industrial dust collection systems have been designed with "self-cleaning" filters for removing dust from an air stream (e.g., see U.S. Pat. No. 4,159,197). These systems have filters (e.g., pleated filters or bag filters) that are cleaned inset (i.e., on-line). For example, while the systems are in use collecting dust, the systems periodically use nozzles to direct pulses of air at the filters in a reverse-flow direction (i.e., in a direction opposite to the flow of air being filtered) to drive or shake collected dust from the filters.
What is needed is an improved device/method for servicing overloaded diesel particulate filters or other exhaust after treatment devices.

Apparatus for cleaning exhaust aftertreatment devices and methods


Provided are a method for fingerprint collection and related products. The method includes the following. In response to a receipt of a fingerprint collection instruction, an intensity of each of ambient lights having at least two different frequencies at a current time point is determined via an optical sensor of the terminal. A target frequency is determined, where the target frequency is a frequency of one ambient light having a lowest ambient light intensity among the ambient lights having the at least two different frequencies. Control light emission of an internal light source of an optical fingerprint sensor of the terminal at least according to the target frequency so as to collect fingerprint data via the optical fingerprint sensor.

With the increasing use of terminals such as smart phones, almost everybody has a smart phone. The existing smart phones generally adopt fingerprint recognition technology. The fingerprint recognition technology can be used in unlocking, mobile payment and other functions of the terminals.
Optical fingerprint recognition technology has good stability and high recognition sensitivity, and thus is widely used in fingerprint sensors of various terminals. The optical fingerprint sensor generally includes a light source and an optical fingerprint detection module. An imaging principle of optical fingerprint recognition is as follows. The light source emits lights, and the lights are reflected to the optical fingerprint sensor after passing through a surface of a display screen pressed by a finger. The optical fingerprint sensor receives the reflected lights and converts the reflected lights into fingerprint data for processing, so as to form a fingerprint image. A principle of fingerprint match is as follows. The optical fingerprint sensor matches the formed fingerprint image with a pre-stored fingerprint image to obtain a matching result.
However, the reflected lights received by the optical fingerprint sensor may be easily affected by ambient lights, which may cause errors in the collected fingerprint data, thereby affecting the result of fingerprint matching.

Method for fingerprint collection and related products

GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.


A method and apparatus for the improved formation of beads or particles. The apparatus comprises a spinning disk including a vibration inducing material. Said vibration inducing material excites the liquid material as it proceeds towards the outer perimeter of said spinning disk, controlling the droplet break-off frequency.

The present exemplary embodiment relates to an apparatus and method for the improved fabrication of small particles, which may also be described as beads or balls. The embodiment finds specialized application in the fabrication of bichromal particles, for a twisting ball display and more specifically to improved control of system parameters resulting in improved uniformity of the final product.
A common procedure for making small particles is known as bead spinning, which involves flowing a liquid onto a spinning disk. The liquid is carried to the outside perimeter of the disk by centrifugal force. Droplets of liquid fly off the edge of the disk and, by drying and/or cooling, solidify. The droplets are collected as solid particles or used to form a film on a surface.
Bichromal balls have hemispheres of contrasting colors and find particular use in "electric paper" displays. Electric paper displays are described in a number of patents including U.S. Pat. Nos. 4,126,854 and 4,143,103 assigned to the present assignee.
One method for making bichromal balls is described in U.S. Pat. No. 5,262,098, which is assigned to the present assignee and is herein fully incorporated by reference. This patent describes an additional step to the traditional bead spinning procedure described above. One liquid is flowed on the top side, of the spinning disk and another liquid is flowed on the bottom side of the same disk. As the disk spins, both liquids are drawn to the outside perimeter of the disk. As the liquids reach the edge of the disk, the liquid on the top of the disk and the liquid on the bottom of the disk merge into a droplet composed of a top side liquid hemisphere and a bottom side liquid hemisphere. The composite droplets then fly off the edge of the disk and solidify prior to landing. When the top side liquid is a contrasting color from the bottom side liquid, a bead with hemispheres of contrasting colors results.
Applications using these particles generally require the particles be very small. The patents cited above refer to bichromal balls in the range of 5 microns to 500 microns. Variations of size and shape of the final product particles may result in nonfunctionality. Due to the ease of nonconformity and the relatively small size of each particle, a wasteful and time-consuming sieving process must be undertaken to narrow the size distribution within that particular batch to an acceptable range.
In an attempt to control the size ranges of the particles and minimize or eliminate the wasteful sieving practice, or improve the uniformity of the film, droplet break-off was analyzed. In both the traditional bead spinning method and the bichromal ball spinning method, the droplet break-off at the edge of the disk is controlled by many factors. These factors include: surface tension, viscosity, the shape of the disk edge, air currents and disk rotations per minute (rpm). Small variations in any of these factors can often result in unacceptable variation in drop size. In an effort to minimize the variations, efforts are made to control the above variables. While some improvement has been seen, the waste from the process is still at undesirable levels.

Acoustic enhancement of particle fabrication by spinning


A method and apparatus for authenticating a device on a wireless network using a secure attestation package is provided. The method includes receiving, by a processor, information related to a device of an Internet of Thing (IoT) service provider, generating, by the processor, a secure attestation package based on the information, transmitting, by the processor, the secure attestation package to the IoT service provider, receiving, by the processor, a request to access a wireless network of the processor from the device of the IoT service provider, and authorizing, by the processor, the device to access the wireless network based on the secure attestation package.

Wireless networks are becoming a ubiquitous platform for enabling a variety of different devices to communicate with other devices. The wireless networks can be used to allow non-traditional communication devices to communicate data for analysis and tracking. For example, Internet of Things (IoT) devices are one class of devices that are growing. However, as IoT devices host unknown functionality and are not fully approved, some components of these devices can be used to attack the wireless networks and create security issues for the service provider of the wireless network, devices on the wireless network, or other networks connected to the wireless network of the service provider.

Secure attestation packages for devices on a wireless network


A highway detection system may include a telematics device associated with a vehicle having one or more sensors arranged therein, a mobile device associated with a user traveling in the vehicle, and a server computer. The server computer may receive traveling data for a trip of the user from the one or more sensors and via the telematics device. The server computer may then determine whether the user is traveling within a city or on a highway based on analysis of the traveling data for the trip of the user, which may include a statistical analysis to calculate standard deviations of metrics in the traveling data. In response to the determination, the server computer may generate a notification to transmit to the user based on whether the user is traveling within a city or on a highway and transmit the notification to the mobile device associated with the user.

Mobile devices, such as smartphones, tablet computers, and other types of mobile computing devices, are becoming increasingly popular for a variety of purposes. In particular, mobile devices, such as smartphones, make people's lives easier by allowing them to connect with various applications and complete different tasks quickly. In some cases, users may utilize their mobile devices while driving in their vehicles to and from various destinations.
For example, a user may rely on a Global Positioning System (GPS) installed on his or her mobile device to navigate to and from destinations. In another example, the GPS may be running in the background of an operating system (OS) installed on a mobile device in order to provide location information and location services to other mobile applications installed on the mobile device. Unfortunately, obtaining location information based on GPS may be battery-intensive and may quickly deplete the battery of a user's mobile device. In other cases, a GPS signal from one or more satellites might not be available for providing location information in certain areas.
Without accessing location information on the user's mobile device, mobile applications might not be able to provide accurate and intuitive services that are customized to each user based on the user's location. Thus, it may be beneficial for mobile devices to obtain location information of a user while traveling in order to provide customized notifications to the user based on the user's location. As such, new systems, methods, and devices may be desired to leverage the capabilities of mobile devices in providing customized services to users in an improved and efficient manner.

Highway detection system for generating customized notifications


An apparatus and method for determining a linear position from a linear variable differential transformer (LVDT) including a primary coil driven by an excitation signal, and two secondary coils coupled to two correlated signals. The method includes converting the correlated signals to a digital estimate, for each of the correlated signals, and evaluating an amplitude of the correlated signals to determine the linear position. The process of converting the correlated signals comprises comparing the correlated signal to an analog feedback signal to generate a comparison result and incrementally adjusting the digital estimate in response to sampling the comparison result at an estimation frequency. The converting process also includes converting the digital estimate to the analog feedback signal, collecting a digital estimate history at a sample frequency that is a binary multiple of the excitation frequency, and analyzing the digital estimate history to determine the amplitude substantially near the excitation frequency.

1. Field of the Invention
This invention relates generally to determining linear position and, more particularly, to using digital means for determining linear position.
2. Description of Related Art
This invention relates to determining linear position by using the electrical outputs of a Linear Variable Differential Transformer (LVDT). It may be desirable to determine a linear position for many applications, for example, actuation systems on aircraft or rocket motors. One method of doing this is to use a LVDT to sense the position. The LVDT may use a sinusoidal excitation and measurement of two inductively coupled output signals. LVDTs have one primary winding and two secondary windings. The two secondary windings are mechanically arranged so an excitation signal on the primary winding will proportionally couple onto the secondary windings based on the position of a ferrous core. By measuring the voltages on the secondary windings it is possible to determine the linear position of the LVDT.
These output signals from the two secondary windings are generally analog signals, which may require a significant amount of analog electronics to evaluate the signal amplitudes and derive the shaft position. As a result, many proposals use analog-to-digital converters to convert the analog signals to digital signals, which may then be manipulated digitally to determine the respective amplitudes and calculate arithmetic functions to determine the shaft position. However, even these solutions may require complex analog-to-digital converters, and complex arithmetic engines for determining the signal amplitudes.
There is a need for a method and apparatus that reduces the complexity and number of analog components used in determining linear position by using simple analog components coupled to flexible digital logic and digital signal processing.

Digital method and apparatus for sensing position with a linear variable differential transformer


Devices, systems, and methods of the present disclosure are directed to dispensing wipes that are treated as the wipes move through a housing of a dispenser. Such in situ treatment of the wipes may facilitate, for example, achieving control over one or more of the concentration, composition, or distribution of one or more chemicals carried by the wipes. Further, or instead, the one or more chemicals may be formed within the housing (e.g., just prior to treating the wipes), which may be useful for treating the wipes with chemicals that have limited stability and/or for reducing chemical handling requirements along a supply chain.

Dispensers are commonly used to dispense handheld wipes that are pre-wet with chemicals for various cleaning applications. While convenient, the chemicals used to pre-wet these wipes are typically limited to stable chemical solutions or the like that are shelf-stable, and can be stored in a container with the wipes prior to use. There remains a need for dispensers that treat wipes with customized chemical formulations as needed, e.g., as the wipes are dispensed from a container.


The invention describes a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator. The developing solvent comprises an aromatic compound of the general formula I ##STR1## wherein R.sup.1 to R.sup.4 are the same or different and denote hydrogen, (C.sub.1 -C.sub.5)n-alkyl or iso-alkyl and R.sup.1 and R.sup.2, provided that R.sup.1 and R.sup.2 are directly adjacent, may also form a cycloaliphatic or aromatic ring having 5 or 6 carbon atoms as ring members which are preferably non-substituted,. provided that the sum of carbon atoms of the substituents and ring members is from 9 to 13. Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer, has a high capacity for layer components and is capable of developing plates based on nitrile rubber.

The invention relates to a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator.
It has long been known to produce relief forms, in particular flexographic printing plates, by means of photopolymerization-crosslinkable layers which are exposed imagewise and thereafter developed and washed out.
For the production of these forms, the photopolymer layer is exposed imagewise to actinic light; a relief can then be formed by washing off the non-exposed and thus non-crosslinked portions of the layer, using a developing solvent. The developing solvent should dissolve the non-crosslinked portions of the layer as quickly as possible, and the solvent must be removable with greatest possible ease from the crosslinked portions of the layer, so that the plate is rapidly dried. For this reason, low-boiling developing solvents presently are generally used.
Examples of preferred solvents which are described in DE-A 22 15 090 include methyl ethyl ketone, benzene, toluene, xylene, carbon tetrachloride, trichloroethane, trichlcoroethylene, methyl chloroform and tetrachloroethane, and mixtures of these.
It is a disadvantage of the above-indicated chlorinated hydrocarbons that they are toxic and give rise to disposal problems. If chlorinated hydrocarbons are used as developing solvents, the portions of the layer which are to be removed swell very strongly while still on the plate and as the concentration of dissolved components of the non-crosslinked layer portions increases in the developing solvent, viscosity of the solvent rises sharply. As a result, the capacity of the developing solvent is very limited and the solvent is rendered useless, already at a solids content of 5%. A further consequence of the strong increase in viscosity is that plates develop very slowly even at less than 5% solids content. In addition, development of plates which contain nitrile rubbers as the elastomers is very slow.
Of the non-chlorinated hydrocarbons specified in DE-A 22 15 090 benzene, toluene and xylene are mentioned. These solvents have the disadvantage of being easily flammable, moreover, they lead to severe swelling of the layer and, consequently, to slow developing and drying of the plate.
Additionally, due to their low flash-point, these solvents cannot be used in developing apparatuses which are not explosion-proof.
DE-A 36 00 116 describes relatively highly boiling developing solvents which contain hydrocarbons, alcohols or ketones which are branched, or cyclic with one or three olefinic double bonds, or saturated, or cycloaliphatic with one to three olefinic double bonds. Monoterpenes are mentioned in particular. Limonene which is used in the example may have good developing characteristics, but is sensitive to oxygen and irritates the skin, properties which should not be present in a developing solvent. It is also a disadvantage of limonene that it permits only very slow development and is difficult to remove from the layer. Furthermore, plates containing nitrile rubbers cannot be developed within reasonable time.

Developing solvent for layers which are crosslinkable by photopolymerization and process for the production of relief forms