A method and apparatus for power control on a first channel that is shared by multiple mobile stations transmitting to base stations in a telecommunication system. An initial mobile station transmission power level is set on the first channel that is shared in the random access mode. The transmission power level may be determined based on a desired performance level of the first channel. The method and system may be efficiently applied on a channel that carries a transmission in one or more bursts, with each burst including the same or a varying number of frames of varying sizes. The method and apparatus utilizes a second channel that is shared by multiple mobile stations for transmitting the power control signaling from the base stations to the mobile stations.

This invention relates to power control in cellular telecommunication systems and, more particularly, to a method and system for power control on a common channel that may be shared by a plurality of mobile stations operating in a cellular telecommunication system.
Power control for mobile station transmissions is an important aspect of cellular telecommunication systems. One type of cellular technology in which power control is particularly important is code division multiple access (CDMA) technology. In a CDMA-type system multiple users, each using a channel identified by a uniquely assigned digital code, simultaneously communicate with the system while sharing the same wideband frequency spectrum. In a CDMA cellular system, the signals from multiple mobile stations are received at the same frequency simultaneously at a base station. Because of the nature of CDMA demodulation, it is necessary that the signal received at the base station from each mobile station be as close as possible to a single power level so that the signal from one mobile station does not overwhelm the signal from another mobile station (near-far problem).
In a CDMA cellular system a power control process may be used to control each mobile station""s transmission power level so that the signal level received at the base station from each mobile station is as close as possible to a single predetermined level. Additionally, the power control process may also be used to assure that the received signal levels at the base station are of an adequate level, so that calls are not dropped. One example of a CDMA mobile station power control scheme is the power control used by systems specified in the
Telecommunications Industry Association/Electronic Industries Association (TIA/EIA) IS-95 standard. Another related CDMA mobile station power control scheme is the power control used by systems specified in the ANSI-008 standard, which is the personal communications system (PCS) 1900 MHz version of IS-95.
In IS-95, a mobile station first adjusts its transmission power level using an access channel assigned to a base station through which the mobile station is attempting to gain access to the system. To gain access, the mobile station follows an open loop power control process that involves transmitting access probe transmissions at a relatively low power level on the access channel and gradually increasing the level of subsequent access probe transmissions in access probe correction increments set by the system, until a response is obtained from the system and the mobile station gains access to the system. The access probe includes an access preamble and an access channel message capsule. The transmission power of each access probe transmission on the access channel is given by the equation:                                                                         Mean                                                  xe2x80x83                                                output                                                  xe2x80x83                                                power                                                  xe2x80x83                                                                  (                  dBm                  )                                            =                              xe2x80x83                                                                            -                  mean                                                                  xe2x80x83                                                input                                                  xe2x80x83                                                power                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                          -                73                                                                                xe2x80x83                                                                            +                  NOM_PWR                                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                                            +                  INIT_PWR                                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                                            +                                      xe2x80x83                                                      the                                                                  xe2x80x83                                                sum                                                  xe2x80x83                                                of                                                  xe2x80x83                                                all                                                  xe2x80x83                                                access                                                          xe2x80x83                                                                                xe2x80x83                                                          probe                                                  xe2x80x83                                                corrections                                                                        (        1        )
The values NOM_PWR and INIT_PWR are system parameters having values assigned by the system. The mean input power is the total received power at the mobile station antenna connector.
The ANSI-008 standard equation is similar but, because of the frequency difference, has a constant equal to 76 instead of 73 and also includes an additional value that is added to increase the range of NOM_PWR, the additional value being defined as 16*NOM_PWR_EXT, which is a system parameter. IS-95 could also be modfied to include a similar value.
Once the mobile station gains access to the system, it waits in an idle mode until a call is initiated from either the mobile station to the base station, or from the base station to the mobile station. A dedicated reverse traffic channel and a dedicated forward traffic channel are then assigned for the call. When transmitting on the IS-95 reverse traffic channel, the mobile station initializes at the power level at which access was obtained on the access channel using the open loop process defined by equation (1). Once the reverse traffic channel transmission power level is initialized and the call begins, the system and mobile station then also begin a closed loop power control process. The closed loop power control process allows the signal level received at the base station from each mobile station transmitting on a reverse traffic channel to be set as close as possible to a single predetermined level. In the closed loop power control process, the base station transmits closed loop power control corrections in the form of power control bits to the mobile station that are transmitted in a power control subchannel that is included in the forward traffic channel. A single power control bit is transmitted in the power control subchannel every 1.25 msec. A xe2x80x9conexe2x80x9d bit transmitted in the power control subchannel indicates that the mobile station should increase its transmission power 1 dB, while a xe2x80x9czeroxe2x80x9d bit indicates that the mobile station should decrease its transmission power 1 dB. Each time a valid control bit is received at the mobile station in the power control subchannel, the mobile station adjusts its output power level up or down in an increment of 1 dB. The mobile station is capable of adjusting the transmission power within a range of xc2x124 dB around the level set by the open loop power control process on the access channel and, as the call is ongoing, the transmission power of the mobile station on the reverse traffic channel is adjusted so that a desired power level is reached and maintained. The mobile station also simultaneously continues the open loop power control process, this time using the forward traffic channel. In the open loop process the mean input power received on the forward traffic channel is the determining value. When involved in the call, the inputs that effect changes in the mobile station""s transmission power are the mean input power as received from the base station on the forward traffic channel and the closed loop power corrections indicated by the power control bits received on the forward power control channel. During a call, the mobile station output power level on the reverse traffic channel is given by the equation:                                                                         Mean                                                  xe2x80x83                                                output                                                  xe2x80x83                                                power                                                  xe2x80x83                                                                  (                  dBm                  )                                            =                              xe2x80x83                                                                            -                  mean                                                                  xe2x80x83                                                input                                                  xe2x80x83                                                power                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                          -                73                                                                                xe2x80x83                                                                            +                  NOM_PWR                                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                                            +                  INIT_PWR                                                                  xe2x80x83                                                                  (                  dBm                  )                                                                                xe2x80x83                                                                            +                                      xe2x80x83                                                      the                                                                  xe2x80x83                                                sum                                                  xe2x80x83                                                of                                                  xe2x80x83                                                all                                                  xe2x80x83                                                access                                                          xe2x80x83                                                                                xe2x80x83                                                          probe                                                  xe2x80x83                                                corrections                                                                                xe2x80x83                                                                            +                                      xe2x80x83                                                      the                                                                  xe2x80x83                                                sum                                                  xe2x80x83                                                of                                                  xe2x80x83                                                all                                                  xe2x80x83                                                closed                                                  xe2x80x83                                                loop                                                                                xe2x80x83                                                          power                                                  xe2x80x83                                                control                                                  xe2x80x83                                                corrections                                                                        (        2        )
As for equation (1), the ANSI-008 standard equation is similar but, because of the frequency difference, has a constant equal to 76 instead of 73 and also includes an additional value that is added to increase the range of NOM_PWR, the additional value defined as 16*NOM_PWR_EXT, which is a system parameter.
A third generation CDMA system is being developed to provide more sophisticated and better services (data, etc.) than provided by IS-95 and eventually to replace IS-95. In the proposed standard for third generation CDMA known as CDMA 2000 TTU-R RTT, it has been proposed that third generation systems have a common control channel that is not used in IS-95. The reverse common control channel (R-CCCH) has been proposed as a common random access channel to be shared by multiple mobile stations to allow transmissions to the system without explicit authorization by a base station. It is planned that the R-CCCH be used for control signaling and data transmissions. Each R-CCCH is distinguished by a different long code. Each R-CCCH also has a corresponding forward common control channel (F-CCCH) that carries transmissions from a base station. The F-CCCH is shared by multiple mobile stations with each data or control signaling transmission on the F-CCCH including address information indicating the particular mobile station to which it is addressed. Data transmitted on the R-CCCH would be included in the access channel message capsule portion of the access probe. In the CDMA 2000 TTU-R RTT standard, it is proposed that the same type of access probe sequence power control as used for the access channel in IS-95 be used for transmission on the R-CCCH.
Because of differences between IS-95 and third-generation systems, the use of IS-95 access channel or similar type power control on the R-CCCH could cause problems in third generation CDMA systems. If the access probe sequence type is begun and received at too high a transmission power, the base station will not signal the mobile station to adjust its transmission power downward during the transmission and the R-CCCH transmission may disturb transmissions of other mobile stations. Also, the F-CCCH is shared by multiple mobile stations, and transmissions on the R-CCCH may be made in one or more bursts, with each burst including the same or a varying number of frames. With the third generation system R-CCCH potentially carrying a substantial amount of data and signaling, capacity could be lost due to delay from the need to transmit an overly long access probe sequence in order to receive acknowledgment, when the access probe sequence is begun at too low a power level.
It is an object and advantage of this invention to provide a method and system for power control on a channel that is shared by multiple users in a telecommunication system.
Another object and advantage of this invention is to provide a method and system for power control on a channel that is shared by multiple users through random access in a telecommunication system.
A further object and advantage of this invention is to provide a method and system for power control on a channel that carries transmissions in one or more bursts, with each burst including the same or a varying number of frames of varying sizes.
The present invention provides a method and apparatus for power control on a channel that is shared by multiple mobile stations transmitting to base stations in a telecommunication system. The mobile stations may share the channel in the random access mode. The method and apparatus allows the system to set an initial mobile station transmission power level and may be efficiently applied on a channel that carries a transmission in one or more bursts, with each burst including the same or a varying number of frames of varying sizes. The method and apparatus utilizes a common channel that is shared by multiple mobile stations for transmitting the power control signaling from the base station to the mobile station.
In an embodiment of the invention, the method and system is implemented on a reverse common control channel (R-CCCH) of a code division multiple access (CDMA) system. Prior to the transmission of data or control information by a mobile on the R-CCCH, a parameter measurement is performed at the base station on a reverse measurement channel that is associated with the R-CCCH and has a transmission power level that has a predetermined relationship with the transmission power level of the R-CCCH. The reverse measurement channel may be a reverse pilot channel associated with the R-CCCH, and the measurements may be performed during an initial access probe from the mobile station on the R-CCCH. A power value associated with the parameter measured on the measurement channel is then determined. The power value may indicate the ratio of the energy per bit, Eb to the effective noise power spectral density, Nt, value for both the R-CCCH and measurement channel combined. The power value is compared to a predetermined threshold power value in the base station. In the embodiment, the predetermined threshold power value that is compared to the power value may be determined based on a probability of frame error rate that is associated with a desired probability of a transmission on the R-CCCH being successful. The predetermined threshold power value may indicate a threshold ratio of energy per bit, Eb to the effective noise power spectral density, Nt, for both the R-CCCH and measurement channel combined. The base station then transmits a power control message to the mobile station that includes a power control command indicating a power control increment or, alternatively, a transmission power level for the mobile station on the R-CCCH according to the comparison of the power value and the predetermined threshold power value. The power control message may be transmitted to the mobile station on a forward common control channel (F-CCCH). After receiving the power control message, the mobile station transmits the data or control information using an initial transmission power according to the power control command. During the transmission on the R-CCCH, multiple measurements are made on the reverse measurement channel. The time interval Tm between the measurements may be based upon the sizes of the frames available on the F-CCCH for sending the power control messages. The F-CCCH may have multiple frame sizes available. In the embodiment, F-CCCH frame sizes of 5 msec, 10 msec or 20 msec are used, giving a Tm of 5 msec, 10 msec or 20 msec and a power control update frequency of 200 Hz, 100 Hz or 50 Hz. Each power control message may include the electronic serial number (ESN) of the mobile station to which the base station is transmitting the power control message. If a burst of N frames transmitted by the mobile station after receiving the power control message, including the power command, results in a frame error rate greater than the rate used to determine the threshold power value used to generate the power control command, the transmission of the burst may be repeated using a new threshold power level that is determined from a frame error rate that is assigned with a successively higher probability of a burst on the R-CCCH being successful, until the burst is received correctly or a timeout occurs.

Method and apparatus for power control on a common channel in a telecommunication system


A system and method for the simplification of data structures, particularly those used for wireless communications, encodes data structures for efficient storage and access. Wireless devices are provisioned with user applications for accessing remote services, such as World Wide Web services. The user applications comprise a plurality of component definitions which typically describe complex data structures for execution by a runtime environment. The runtime environment is conditioned to use a manner to encode such data structures in flat arrays of primitive types.

The acceptance of wireless devices as a preferred personal communications medium has created a growing demand for such devices. Users of such devices also increasingly expect more functionality and a broader range of services to be made available through such devices. Not only is there a demand for more functionality, there is also a demand for faster response times and more efficient access to remote services.
A major challenge is faced in exposing wireless devices to complex data sources, such as web services, due to the size and complexity of the data structures communicated from such sources. In wired networks and devices where resources and efficiency are not a significant concern, it is permissible to transmit, process and store large and complex data structures.
Complex data structures containing many objects and levels of nesting introduce a significant memory overhead on wireless devices. This impacts performance when storing to and retrieving from a memory store.
Consequently, what is desired is a method and apparatus to efficiently encode complex data structures of an application definition.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.

Apparatus and method for efficient encoding of application definition using contiguous arrays


A semiconductor device includes a semiconductor substrate, a lower wiring layer formed on the semiconductor substrate, a first interlayer insulating film formed on the lower wiring layer and including a first upper surface and a second upper surface, the first upper surface being higher than the second upper surface relative to a surface of the semiconductor substrate, a contact plug formed in the interlayer insulating film and including a first bottom surface contacting to the lower wiring layer, a third upper surface flush with the second upper surface and a fourth upper surface flush with the first upper surface, an upper wiring layer formed on the first and third upper surfaces and including a first side surface and a second side surface opposite to the first side surface, and a second interlayer insulating film formed on the second and fourth upper surfaces.

1. Field of the Invention
The present invention relates to a semiconductor device having a multilayer wiring structure.
2. Description of the Related Art
Semiconductor devices have been making progress in high integration year by year, and a reduction in the rules of circuit design has been introduced as the requirement for miniaturization. The reduction in the circuit design rules is directly related to a reduction in a circuit area. For example, in an integrated circuit having a multilayer wiring structure, a distance between adjacently formed via holes is reduced such that a distance between each via hole and metal wiring formed in an upper layer is also reduced at the same time.
Such a reduction in the distance between each via hole and the metal wiring further reduces a positioning margin in a lithography process, which renders the processing technique difficult. In addition, since a distance between adjacent wiring patterns is reduced, it becomes difficult to obtain a desired insulating property. When a sufficient distance of insulation is not obtained, there arises a problem of failure due to short circuit such as dielectric breakdown or direct short circuit or a problem of parasitic capacitance, resulting in a difficulty in achieving a stable device operation.
FIGS. 10A to 11B illustrate an example of the foregoing circumstances. FIG. 10A shows an example of multilayer wiring structure having no occurrence of patterning misalignment, whereas FIG. 10B shows an example of multilayer wiring structure in which misalignment has resulted from the patterning. As shown in these figures, an Al—Cu layer 2 serving as a lower wiring layer is formed on a silicon substrate 1. A titanium nitride (TiN) layer 3 serving as a barrier metal is formed on the Al—Cu layer 2. An interlayer wiring layer 4 is formed on the TiN layer 3. The interlayer wiring layer 4 has via holes each formed so as to extend vertically through a predetermined part of a dual tetraethyl orthosilane (d-TEOS) film 5. Contact plugs 6a and 6b made from tungsten (W) or the like are formed in the via holes respectively.
Barrier metal layers 7a and 7b each serving as an upper wiring layer, Al—Cu layers 8a and 8b and barrier metal layers 9a and 9b are patterned on the top of the interlayer wiring layer 4 so as to correspond to the locations of the contact plugs 6a and 6b. A distance d0 between electrodes in the upper wiring layer is, for example, 80 nm. In the case of FIG. 10B, there is an amount of misalignment A in the patterning of the upper wiring layer.
FIGS. 11A and 11B are sectional views corresponding to parts of the fabrication process respectively. As shown in FIG. 11A, the Al—Cu layer 2 and TiN film 3 of the lower wiring layer are formed, and the d-TEOS film 5 with a film thickness of 500 nm is formed on the TiN film 3. Tungsten as a material for the contact plugs 6a and 6b is embedded in the via holes respectively.
In the state as shown in FIG. 11A, the TiN film 7, the Al—Cu film 8 of the upper wiring layer material and the TiN film 9 are formed on the d-TEOS film 5 serving as an interlayer insulating film, and resists 10a and 10b corresponding to a wiring circuit are patterned as shown in FIG. 11B. Misalignment occurs during a lithography process and an amount of misalignment A is, for example, 50 nm.
The TiN film 9, Al—Cu film 8 and TiN film 7 are etched by a reactive ion etching (RIE) process using a gas plasma such that the structure as shown in FIG. 10B is obtained. In this case, the TiN films 9a and 9b, Al—Cu films 8a and 8b, and TiN films 7a and 7b are electrically connected to the tungsten plugs 6a and 6b while misalignment has occurred by the misalignment amount A.
When the misalignment amount A is, for example, 30 nm as the result of occurrence of the foregoing misalignment, an insulation distance d1 between the upper wiring layer of the TiN film 9a, Al—Cu film 8a and TiN film 7a and the adjacent tungsten 6b becomes 50 nm. As a result, since a sufficient insulation distance can be ensured, no problem arises in the operation of the device. However, the insulation distance d1 becomes 30 nm when the misalignment amount A is increased to 50 nm. Consequently, there is a possibility of occurrence of a short circuit or an increase in the parasitic capacitance.
As one of conventional countermeasures, the specification of positioning in the lithography process has been reconsidered and/or the diameters of the via holes have been reduced. However, the reduction in the circuit design rules makes it difficult to obtain an insulation distance and at the same time, it is quite difficult to carry out further reconsideration of the positioning specification in view of the device performance. Further, variations in the diameter of the via hole also make it difficult to obtain a stable distance between insulators. Still further, at the same time, even when the diameter of the via hole is reduced, such reduction directly results in reduction in a junction area. As a result, a desired operation of the device cannot be achieved. Thus, the foregoing problem needs to be overcome for future fabrication of semiconductor circuits.
Accordingly, securement of the insulation distance and prevention of failure due to short circuit or parasitic capacitance are particularly important in the fabrication of multilayer wiring circuits in order that a stable device operation may be obtained against miniaturization of the device. JP-A-2000-208615 and JP-A-2002-176098 disclose the foregoing countermeasures.
JP-A-2000-208615 discloses an interlayer connection structure connecting upper and lower wiring layers of a semiconductor substrate. In this case, even upon occurrence of misalignment during the lithography process, a sufficient distance of electrical insulation can be ensured between contact portions adjacent to each other, whereby a sufficient contact area can be secured.
Further, JP-A-2002-176098 discloses a semiconductor device employing a structure that a lower side contact plug is previously recessed in the formation of a multilayer wiring circuit of a borderless structure so that a contact pattern at an upper wiring layer is prevented from reaching a contact plug due to misalignment, thereby preventing short circuit.
In each of the foregoing references, however, a width of gap differs according to an amount of misalignment at the occasion of an etching process for recessing the contact plug, resulting in a problem of embeddability in the case where an interlayer insulating film is embedded in an upper layer.

Semiconductor device having multilayer wiring structure


A stability control system (24) for an automotive vehicle as includes a plurality of sensors (28-39) sensing the dynamic conditions of the vehicle and a controller controls a steering force to reduce a tire moment so the net moment of the vehicle is counter to the roll direction. The sensors may include a speed sensor (30), a lateral acceleration sensor (32), a roll rate sensor (34), a yaw rate sensor (20) and a longitudinal acceleration sensor (36). The controller (26) is coupled to the speed sensor (30), the lateral acceleration sensor (32), the roll rate sensor (34), the yaw rate sensor (28) and a longitudinal acceleration sensor (36). The controller (26) determines a roll angle estimate in response to lateral acceleration, longitudinal acceleration, roll rate, vehicle speed, and yaw rate. The controller (26) changes a tire force vector using by changing the direction and/or force of the steering actuator in response to the relative roll angle estimate.

1. Technical Field
The present invention relates generally to a dynamic behavior control apparatus for an automotive vehicle, and more specifically, to a method and apparatus for controlling the roll characteristics of the vehicle by controlling the steering direction of the vehicle.
2. Background
Dynamic control systems for automotive vehicles have recently begun to be offered on various products. Dynamic control systems typically control the yaw of the vehicle by controlling the braking effort at the various wheels of the vehicle. Yaw control systems typically compare the desired direction of the vehicle based upon the steering wheel angle and the direction of travel. By regulating the amount of braking at each corner of the vehicle, the desired direction of travel may be maintained. Typically, the dynamic control systems do not address roll of the vehicle. For high profile vehicles in particular, it would be desirable to control the roll over characteristic of the vehicle to maintain the vehicle position with respect to the road. That is, it is desirable to maintain contact of each of the four tires of the vehicle on the road.
Vehicle rollover and tilt control (or body roll) are distinguishable dynamic characteristics. Tilt control maintains the vehicle body on a plane or nearly on a plane parallel to the road surface. Roll over control is maintaining the vehicle wheels on the road surface. One system of tilt control is described in U.S. Pat. No. 5,869,943. The xe2x80x3943 patent uses the combination of yaw control and tilt control to maintain the vehicle body horizontal while turning. The system is used in conjunction with the front outside wheels only. To control tilt, a brake force is applied to the front outside wheels of a turn. In certain maneuvers, however, application of brakes may not be desirable. It would therefore be desirable to provide a roll stability system that detects a potential rollover condition and temporarily applies steering in a desired direction to counter rollover.
It is therefore an object of the invention to provide a roll control system for use in a vehicle using steering direction.
In one aspect of the invention, stability control system for an automotive vehicle includes a plurality of sensors sensing the dynamic conditions of the vehicle and a controller that controls direction to reduce a tire moment so the net moment of the vehicle is counter to the roll direction. The sensors may include a speed sensor, a lateral acceleration sensor, a longitudinal acceleration sensor, a roll rate sensor, and a yaw rate sensor. A controller is coupled to the sensors to determine a roll angle estimate. The controller determines the direction and steering effort change in response to the relative roll angle estimate to counter roll.
In a further aspect of the invention, a method of controlling roll stability of the vehicle comprises the steps of:
determining a roll angle estimate in response to a rollover sensor; and controlling at least one of the front steering actuators to determining a tire force vector in response to the relative roll angle estimate.
One advantage of the invention is that such systems may be easily implemented into a steer-by-wire system.
Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.

Rollover stability control for an automotive vehicle using front wheel actuators


A seat plate folding mechanism provided in a wheelchair or in a transfer device used to transfer of a person between a wheelchair and a bed etc. The mechanism enables easier transfer of a person with crippled limb between a wheelchair and bed, toilet seat, etc. The seat plates are folded, with the surfaces vertically set, to the sides of the occupant, to more rear-upward than an extended position. More particularly, the seat plate folding mechanism has stays whose base end sides are pivotally supported at side frames of a frame and has seat plates, one side of each of which is supported and connected at the head of a stay so as to be pivotable about a front-back shaft. The seat plates are folded by compound motion of swing of the stays and swing of the seat plates, the swing of the stay occurring at the section where the stay is pivotally supported at a side frame, the swing of a seat plate occurring at the section where the seat plate is supported and connected at the stay. The seat plates are folded to sides of the occupant, to more rear-upward than an extended position, with the surfaces vertically set. An L-shaped, reverse L-shaped, or lateral T-shaped stay is used as the stays, and the stays are supported at the side frames of the frame so as to be pivotable about vertical shafts.

Japanese Patent Publication Nos. H5-253260 and H3-188853 (hereinafter referred to as D1 and D2, respectively) described below have proposed a wheelchair having a frame connecting left and right side frames in front of an occupant and transferring the occupant to a bed or like from the rear side by demounting the seat plate and backrest. In addition, Japanese Utility Model Registration No. 3068034 (hereinafter referred to as D3) described below has proposed a walking auxiliaries having foldable seat plates at the sides.
The wheelchair comprises a planar U-shaped or M-shaped frame connecting left and right frames 5 in front of the occupant's lower limbs with an occupant's backside including lower limbs opened; a seat supported on the frame; a space of a side frame opened at the rear so that the edge of the bed can be inserted from the rear to the underside of the seat.
Moreover, in the conventional wheelchair with a folding frame, two sides of the seat are pivotable around an axis running in the front and back directions and connected to side frames at both sides. For a wheelchair with a soft cloth seat, the seat is folded to a V-shape due to its dead weight when the frame is folded. In addition, a wheelchair with a rigid seat plate is folded to an inverted V shape. When the frame is folded, the seat remains attached to the side frame.


Systems for managing downshifts in hybrid-electric vehicles are disclosed. The systems include a multispeed transmission, an internal combustion engine selectively coupled to the multispeed transmission, an electric motor coupled to the multispeed transmission, and an electronic control unit. The electronic control unit is programmed to evaluate a torque demand, start the internal combustion engine, and pre-stage a downshift shift sequence by partially disengaging a second shift clutch and partially engaging a first shift clutch. The electronic control unit is also programmed to interrupt the downshift shift sequence until a pre-determined torque supplemental event occurs and later complete the downshift shift sequence by modifying the hydraulic pressure through the valve body to completely disengage a second gear set from the input shaft with the second shift clutch and completely engage a first gear set and the input shaft with the first shift clutch.

Hybrid-electric vehicles that include an internal combustion engine and an electric motor/generator operate in a variety of operating modes including an electric operating mode, a combustion operating mode, and a combustion/electric operating mode. In general, as torque demand from the driver of the hybrid-electric vehicle increases, the hybrid-electric vehicle may switch from an electric operating mode to a combustion/electric operating mode or to a combustion operating mode. Additionally, an elevated torque demand from the driver may initiate a downshift of the transmission so that the internal combustion engine and/or the electric motor/generator can provide requested torque to the drive wheels of the hybrid-electric vehicle. Transitioning between operating modes may be complicated by driver torque demand, vehicle operating speed, and vehicle operating condition.
Accordingly, systems for managing downshifts in hybrid-electric vehicles may be desired.


A disk array apparatus comprises a casing, a disk drive group configured by a plurality of disk drives, a controller unit configured by a plurality of circuit substrates, a plurality of cooling fans, and backflow prevention members. The plurality of cooling fans is provided so as to be aligned between the disk drive group and the controller unit in the casing. The backflow prevention members are provided so as to protrude on the side of the disk drive group or on the side of the controller unit from between the cooling fans while extending to define a space on the inlet side or the outlet side of the cooling fans.

For the purpose of improving reliability of data storage, a disk array apparatus is configured in such a manner that a plurality of magnetic or optical disk drives is mounted in a casing. The disk array apparatuses are connected with each other through dedicated high-speed network lines such as optical network lines, managed by management software, and utilized as SAN (Storage Area Network) disk array apparatuses, NAS (Network Attached Storage) disk array apparatuses, or a sole RAID (Redundant Array of Inexpensive Disks) disk array apparatus.
Each of the disk drives mounted on these disk array apparatuses is configured by a disk body mounting therein a disk, a driving motor, a head, an actuator, and the like, connectors for connecting electronic components for control, and the like. Main heating sources of the disk drive are the electronic components for control such as the driving motor, the actuator, and an LSI. The heat generated by these components is cooled by cooling air supplied by cooling fans provided in a disk array casing. If the disk array apparatus is poor in cooling capability, the temperature of the disk drives rises or the temperature varies between a plurality of disk drives. As a result, there is concern that the disk array apparatus malfunctions and reliability in the long term is deteriorated. For example, the variation in temperature between a plurality of disk drives causes deviation in timing of electronic circuits, which results in the possibility of a trouble in accessing from a controller to the disk drives and the possibility of a delay in time required to transfer data. Further, if the temperature of the disk drives rises, a lubricating layer applied on the surface of a magnetic disk is deteriorated and the magnetic disk is likely to be damaged.
Furthermore, it is an important issue to reduce noise generated by the cooling fans that are driven to supply cooling air to the disk drives in the disk array apparatus.
Moreover, in the disk array apparatus, reliability in data retention and data processing becomes extremely important. This fact is applied even in the event of a failure in a cooling system of the disk array apparatus itself. That is, even if a part of the fans for cooling the disk array apparatus fails to operate properly, the system needs to be operated without a halt until the repair is completed. In other words, it is necessary to secure cooling redundancy.
In accordance with a system configuration, a plurality of disk array apparatuses are horizontally installed or a sole disk array apparatus is vertically installed on, for example, a standard 19-inch rack in many cases. Accordingly, it is important that the cooling capability including the cooling redundancy is not affected by the installing direction of the casing.
As described above, the important issues for the disk array apparatus are as follows: a disk drive group needs to be cooled uniformly; the cooling redundancy for the disk drives needs to be secured; and noise generated by the cooling fans needs to be cut without being affected by the installing direction of the casing.
In a conventional disk array apparatus, there is shown a technique for preventing the cooling efficiency from rapidly decreasing by providing a shutter so that outside air does not flow back through the cooling fans in the event of a failure of the cooling fans (refer to Japanese Patent Laid-Open No. H11 (1999)-22698).
Further, in a conventional cooling apparatus for electronic devices, there is described a cooling technique in which a plurality of cooling fans are provided in the vicinities of heating components, and all the cooling fans are operated under the normal condition. If any one of the cooling fans fails to operate properly, air volume of the other cooling fans is controlled (refer to Japanese Patent Laid-Open No. 2005-57119).
Further, in a conventional disk array apparatus, there is disclosed a technique for improving a robust property and decay durability of a system by keeping some of a plurality of disk drives always in the standby mode (refer to Japanese Patent Laid-Open No. 2003-280823).
Further, in a disk storage apparatus, there is disclosed a control technique for stopping a write operation or spindle rotations when the temperature of an enclosure exceeds an allowable value due to a failure of the cooling fans (refer to Japanese Patent Laid-Open No. H05 (1993)-234237).
Further, in a conventional electronic device, there is disclosed a control technique in which combinations of a plurality of cooling fans arranged above and below a shelf, and the shelf, are divided into predetermined groups, and if the cooling fans fail to operate properly, an alarm is generated on a group unit basis and the group is made out of system (refer to Japanese Patent Laid-Open No. H03 (1991)-39880).
In the conventional technique according to Japanese Patent Laid-Open No. H11 (1999)-22698, the backflow can be completely prevented from occurring in the event of a failure of the cooling fans. However, since the shutter is opened and closed by its own weight, the installing direction of the casing is largely restricted. Further, there is a case wherein the sufficient amount of cooling air flow can not be obtained due to a large loss of air flow caused by keeping the shutter open. Further, there is a case wherein a slight difference in flow path condition produces a difference in flowing pressure between the plurality of fans, so that the shutter is intermittently opened and closed. In such a case, abnormal noise, which extremely annoys a user, is intermittently generated from the casing of the apparatus.
The conventional technique according to Japanese Patent Laid-Open No. 2005-57119 raises a problem of the air backflow through the cooling fans in the event of a failure of the cooling fans, which is also a problem in the conventional technique according to Japanese Patent Laid-Open No. H11 (1999)-22698. Therefore, it is necessary to prepare a plurality of large cooling fans having large fan properties in order to secure the sufficient amount of cooling air flow necessary and enough to cool all the disk drives in a good condition even in the event of a failure of the cooling fans. This case causes a problem of increasing noise generated by the fan.
The conventional technique according to Japanese Patent Laid-Open No. 2003-280823 allows the load of the disk drives to be equalized, and as a result, the temperature of the disk drives is equalized. However, the technique does not solve the problem that the temperature of the disk drives rises in the event of a failure of the cooling fans.
In the conventional technique according to Japanese Patent Laid-Open No. H05 (1993)-234237, although a control method by the disk drive alone is described, behavior of the whole system in which a plurality of disk drives is aligned is not disclosed.
In the conventional technique according to Japanese Patent Laid-Open No. H03 (1991)-39880, a combination of cooling fans arranged above and below a shelf and the shelf is classified as one group. In the case where a target electronic device is a disk array apparatus, the plurality of disk drives is accommodated in the shelf. In this case, if all the disk drives in the shelf are stopped due to a failure of the cooling fan, the usability of the system in the other disk drive group being operated is decreased, and in addition, the load of the system imposed by saving data for the disk drive group in the stopped shelf to the other disk drive group in the other shelf is increased. Alternatively, in many cases, it is difficult to place a plurality of cooling fans above and below each shelf due to a problem of securing spaces on the locations where the fans are placed and a problem of noise generated by the fans. In such a case, the cooling fans are arranged in front or rear of the shelf. However, in such a configuration, if the cooling fans in the shelf fail to operate properly, the disk drive group in the shelf needs to be stopped immediately and the cooling redundancy can not be secured.
The object of the present invention is to provide a disk array apparatus that enables to uniformly cool a disk drive group, to secure the cooling redundancy of a disk drive group, and to reduce noise generated by cooling fans without being affected by the installing direction of the casing.


A display panel and an organic light-emitting diode (OLED) display including the display panel are disclosed. The display panel includes a first pixel configured to emit a first color of light, a second pixel configured to emit a second color of light, and a third pixel configured to emit a third color of light. Each of the first to third pixels includes a light emission current applying unit including a driving transistor and a storage capacitor, a gate electrode of the driving transistor configured to receive a data signal from a display driver of the OLED display. The panel includes a light emission unit configured to emit light based on a light emission current. The panel also includes an initialization voltage supply unit configured to provide an initialization voltage to the gate electrode of the driving transistor and the first electrode of the OLED.

Field
The described technology generally relates to a pixel, a display panel, and an organic light-emitting diode (OLED) display including the display panel.
Description of the Related Technology
An OLED display can control OLEDs to display images. An electrode of the OLED (e.g., anode) can be initialized by an initial voltage at every frame. As the initialized voltage difference between two electrodes of the OLED increases to a threshold voltage or more to emit light, a parasitic capacitor of the OLED is charged to a specific amount (Q=CV) to have a voltage difference between the two electrodes greater than the threshold voltage. In addition, a green color OLED (i.e., an OLED that emits green color light) generally has higher light emission efficiency than a red color OLED (i.e., an OLED that emits red color light) or a blue color OLED (i.e., an OLED that emits blue color light) such that the green color OLED can have a similar brightness to the other colors using less current. The green color OLED can have less trigger current and greater parasitic capacitance than the red OLED or blue OLED.

Display panel and organic light-emitting diode display including the same


A method is provided to automatically correct an original source code. An abstract syntax tree (AST) is created from the original source code where the AST includes AST nodes. AST node filter queries are evaluated on the AST to filter out AST nodes with defect patterns. Automatic fixes are applied to the filtered AST nodes to transform the AST. A modified source code is created by deserializing the transformed AST.

Coding standard violations, non-conformance to best practices, and defect patterns are abundant in existing source code. These source code issues lead to unmaintainable code and potential bugs in later stages of software life cycle when they are more expensive to fix. It is important to detect and correct these source code problems early in the development cycle when they are less expensive to fix.

Extensible code auto-fix framework based on XML query languages


An optical information medium having a light transmission layer obtained by curing a composition containing a urethane di(meth)acrylate (A) of the formula (I) and the other urethane di(meth)acrylate (B), and having a tensile elastic modulus of 600 to 1300 MPa at 25° C. and a light transmittance of 80% or more at wavelength of 400 nm (in the formula, R1=an alicyclic diisocyanate residue, R2=an alkylene group or an organic group containing a cycloalkyl group or ester bond, R3=H or methyl group.):

Optical information media such as a read-only optical disk and recordable optical disk are recently significantly used as an information recording medium recording and preserving a large amount of information such as a motion picture information. For example, a compact disk among these media generally has a structure in which a reflection layer is formed of a metal thin film on a transparent substrate made of a polycarbonate on which fine grooves, embossed pit trains have been formed, and an organic protective layer having a thickness of about 5 to 20 μm is provided for preventing deterioration of this reflective layer.
On the other hand, for enhancing recording capacity, optical disks obtained by bonding two transparent substrates as described for example in Japanese Patent Application Laid-Open (JP-A) No. 08-212597, namely, DVDs (digital video disk or digital versatile disk) are widely spreading, recently.
Further, as a high density type optical disk capable of enhancing recording capacity further than DVD and recording high quality motion picture information for a long period of time, optical information media described in JP-A No. 08-235638 are suggested. This high density type optical disk is an optical information medium obtained by forming a recording layer on a transparent or opaque supporting substrate formed of plastic, then, laminating a light transmission layer having a thickness of about 100 μm on the recording layer, which is used by being irradiated with recording light and/or reading light through the light transmission layer.
Regarding a high density type optical disk, there is suggested further increase in density by short wavelength recording utilizing laser light having wavelength shorter than red laser, for example, having a wavelength of 400 nm, used for recording and/or reading of conventional optical information media such as a compact disk and DVD, as described in JP-A No. 11-273147.
As a method of forming a light transmission layer, there are listed, for example, (1) a method of bonding a film of a thermoplastic material such as a polycarbonate or a glass plate on a recording layer using an ultraviolet-curable resin, (2) a method of applying an ultraviolet-curable resin on a recording layer by a spin coat method, then, irradiating with ultraviolet to obtain a light transmission layer, as described in JP-A No. 08-235638.
When a thermoplastic transparent plastic film is used in the above-mentioned light transmission layer forming method (1) described in JP-A No. 08-235638, there is a problem of deterioration in its scratch resistance, and when a glass plate is pasted, there is a problem that weight is large and handling is inferior though scratch resistance is superior. There is also a problem that a light transmission layer made of glass cracks easily by impact from outside.
As ultraviolet-curable resins usable in the above-mentioned light transmission layer forming method (2), there are mentioned ultraviolet-curable resins described in JP-A No. 03-131605. However, a light transmission layer is formed using this curable resin, its scratch resistance is more excellent than that of a transparent film made of plastic as described above, however, since transmittance for light having a wavelength of about 400 nm is low, short wavelength recording is difficult, and since the curable resin shows high volume shrinkage in curing, significant skew occurs on an optical disk, these being practical problems.


An endothermic hydrocarbon fuel system to avoid thermally induced coking on the catalytic surfaces of an heat exchanger used as a reactor to dehydrogenate the fuel so that it provides a heat sink for the heat exchanger for cooling parts of high speed aircraft. The invention provides a means to feed an acceptable concentration of hydrogen to the reactor feed stock, wherein the feed stock is a portion of the endothermic hydrocarbon fuel that is catalytically dehydrogenated to provide a heat sink. The preferred embodiment uses Methylcyclohexane as a fuel and provides a return loop to recycle a fraction of the reaction products to provide the hydrogen to the reactor feedstock.

1. Field of the Invention
This invention relates to heat exchangers that are used as reactors to catalytically dehydrogenate endothermic hydrocarbon fuels in propulsion systems with particular application to gas turbine engine combustors. The present invention provides apparatus and methods for avoiding thermally induced fuel deposits on the catalytic surfaces of these reactor heat exchangers.
2. Description of Related Art
It is well known to design aircraft propulsion systems to use endothermic hydrocarbon fuels. Endothermic fuels hold the potential for significantly increasing the performance of gas turbine and other engines as a result of their heat sink potential. One particularly important endothermic hydrocarbon fuel is Methylcyclohexane (MCH) which can be catalytically converted to toluene and hydrogen with a theoretical absorption of 1959 Btu/lbm. This example includes both the sensible and chemical absorption of heat and assumes a 99% conversion and that the fuel was heated from 70.degree. F. to 1340.degree. F.
The practical implementation of converting MCH to toluene and hydrogen requires the use of a heterogeneous catalyst. Reforming catalysts conventionally used in the conversion of petroleum naphtha feedstocks to high octane gasoline are also used in the present invention. These catalysts essentially dehydrogenate cyclo paraffinic reactants to produce the desired result. Such catalysts include, but are not limited to Pt-Al2O3, Pt-Re-Al2O3, and Pt-Ir-Al2O3. Over the range of temperatures and pressures in which these reactions typically occur (400.degree.-900.degree. K. and 1 to 150 atmospheres) competing reactions take place which include cracking, re-hydrogenation, and coke formation. The formation of coke in particular, is a problem as it tends to strongly adsorb on the surface of the catalyst, fouling active sites and reducing catalyst surface area and pore passages, thereby reducing overall catalytic activity.
It has been reported in the petroleum industry that the inclusion of hydrogen (H2) in the reactant feed suppresses the formation of coke, see "Catalytic Reforming of Naphtha in Petroleum Refineries" by M. Dean Edgar, published in Applied Industrial Catalysis, Volume 1, 1983; "Coke Tolerance of Catalytic Reforming Catalysts" by In-Sik Nam, John W. Eldridge, and J. R. Kittrell, published in Ind. Eng. Prod. Res. Dev., 1985; and "Reaction Kinetics of Methylcyclohexane Dehydrogenation over a Sulfided Pt+Re/Al2O3 Reforming Catalyst" by Michael A. Pacheco and Eugene E. Petersen, published in Journal Of Catalysis, 1985.

Reducing thermal deposits in endothermic fuel reactors of propulsion systems


There is provided a piezoelectric ceramic having a small mechanical factor of merit Qm and excellent heat-resisting properties, e.g., a piezoelectric ceramic for filter elements which is compatible with surface mounting and a method of manufacturing the same in a large amount and in a stable manner. There is provided a piezoelectric ceramic which is a composite oxide of at least lead, zirconium and titanium, wherein an oxide of manganese exists in a grain boundary layer in a density higher than that in a crystal grain of the piezoelectric ceramic and a glass phase exists in the grain boundary layer. It is manufactured by depositing a manganese compound and a glass material on the surface of a piezoelectric ceramic comprising a composite oxide of at least lead, zirconium and titanium and by performing thermal processing thereafter to diffuse the deposited substance in a grain boundary portion of the piezoelectric ceramic.

1. Field of the Invention
The present invention relates to a piezoelectric ceramic to be used in surface mount type piezoelectric components which must be resistant to heat and a method of manufacturing the same.
2. Description of the Related Art
As piezoelectric ceramics used in ceramic filters and the like, piezoelectric ceramics mainly composed of lead zirconate titanate (PZT or Pb(Ti.sub.x Zr.sub.1-x)O.sub.3) or the like have been widely used. Materials used for ceramic filters which have excellent characteristics in that group delay time (GDT) characteristics are flat and phase distortion is small, must have a small mechanical factor of merit Qm. In order to improve the piezoelectric characteristics of such ceramics, various additives in very small amounts have been added to them. Known materials include those obtained by adding niobium oxide, antimony oxide, tantalum oxide and the like as additives to lead titanate zirconate and those obtained by substituting rare earth elements such as Sr, Ba, Ca and La for a part of Pb atoms in lead titanate zirconate.
However, piezoelectric ceramics having a small Qm value as described above have had a shortcoming in that even such a ceramic having a high Curie point suffers shifts in resonant and antiresonant frequencies at elevated temperatures because of a decrease in the electromechanical coupling factor K when the electrodes formed on both ends of the piezoelectric ceramic are opened. This has resulted in a problem in that such a ceramic used as a surface mount type filter element suffers reduction in filter characteristics when exposed to a high temperature (about 250.degree. C.) during reflow soldering.
As a solution to this problem, it has been reported that the specific resistance of a grain boundary portion of a piezoelectric ceramic having a small Qm value and a high Curie point can be reduced to improve heat-resisting properties by thermally diffusing a manganese compound from the surface of the piezoelectric ceramic to distribute an oxide of manganese unevenly so that it concentrates in the grain boundary layer in a high density. See, e.g., JP-A-6-1655, JP-A-6-1656 and JP-A-1657.
However, there has been a problem from the viewpoint of manufacture in that the thermal diffusion of the manganese compound from the surface of the piezoelectric ceramic causes a change in the structure of the grain boundary of a piezoelectric ceramic which has been sintered in advance and in that characteristics significantly vary if the amount of Pb in the piezoelectric ceramic fluctuates due to evaporation during manufacturing or if the temperature distribution in the thermal diffusion furnace is great. Therefore, it has been difficult to perform thermal diffusion in a large amount and in a stable manner, which has made the reduction in the specific resistance of a grain boundary portion insufficient to improve heat-resisting properties.
It is therefore an object of the present invention to provide a piezoelectric ceramic in which the above-described problems are solved and which has a small mechanical factor of merit Qm and excellent heat-resisting properties, e.g., a piezoelectric ceramic for filter elements which is compatible with surface mounting and a method for manufacturing the same in a large amount and in a stable manner.

Piezoelectric ceramic and manufacturing method thereof


A dashboard device of a vehicle includes a storage component and a processor. The storage component stores a plurality of different language packs and a first national table listing a first number of unique language indices associated respectively with the language packs. The processor is coupled to the storage component and is programmed to, in response to receipt of a machine code and a second number related to another plurality of unique language indices from a portable electronic device, use one of the language packs to set language used on the dashboard device based on content of the machine code and a relationship between the first and second numbers.

Taiwanese Patent No. 1380229 discloses a guiding system having radio frequency identification. As shown in FIG. 1, a set 921 of radio frequency identification (RFID) units 9211-9215 are disposed on an object 923 (e.g., a billboard, a display screen, etc.). Each of the RFID units 9211-9215 stores guiding information corresponding to the object in a specific language. For example, the RFID unit 9211 may store guiding information in Mandarin Chinese, the RFID unit 9212 may store guiding information in French, the RFID unit 9213 may store guiding information in English, the RFID unit 9214 may store guiding information in Korean, and the RFID unit 9215 may store guiding information in Japanese. A user may use a handheld device 922 (e.g., an audio player, a mobile phone, etc.) to receive the guiding information of a specific language from one of the RFID units 9211-9215 (e.g., the RFID unit 9214). Afterward, the user may operate the handheld device 922 to play the guiding information in the form of audio using a speaker 927, and/or to display the guiding information using a screen 928.

System for setting a language for a dashboard device of a vehicle


A system for measuring health data includes a measurement device. The measurement device includes at least one measurement interface to receive a first fluid sample, a processor to measure one or more first characteristics of the first fluid sample, and at least one memory device to store first data. The processor reads the first data and measures the one or more first characteristics of the first fluid sample according to the first data. The at least one memory device also stores second data. The processor reads the second data instead of the first data to reconfigure the measurement device and measures one or more second characteristics of a second fluid sample according to the second data. An external processing device may be communicatively coupled to the measurement device and may execute a healthcare application that communicates with the measurement device and may be employed to reconfigure the measurement device.

The quantitative determination of analytes in body fluids is of great importance in the diagnoses and maintenance of certain physiological conditions. For example, persons with diabetes (PWDs) frequently check the glucose level in their bodily fluids. The results of such tests can be used to regulate the glucose intake in their diets and/or to determine whether insulin or other medication needs to be administered.
A PWD typically uses a measurement device (e.g., a blood glucose meter) that calculates the glucose concentration in a fluid sample from the PWD. The measurement device operates by measuring a raw electrochemical or optical signal from a reaction between a reagent and the glucose in the sample. Currently, electrochemical or optical measurement devices are designed and programmed to employ a hardcoded measurement sequence to obtain the raw signal. The measurement devices then use a calculation sequence to process the raw signal data according to a hardcoded algorithm. The measurement sequence instructs the measurement device how to perform the actual measurement electrochemically or optically and how to obtain an electrochemical or optical signal as raw measurement data. The calculation sequence instructs the measurement device how to convert the raw measurement data into a final measurement value (e.g., blood glucose concentration expressed as milligrams per deciliter (mg/dL)) that can be communicated to the PWD. The measurement sequence and calculation sequence are hardcoded into the measurement device, and the measurement device is limited to operating according to these specific sequences.


The incinerator has a closed housing (10) with high temperature insulation (17). A linear gas burner (50) is wholly within the bottom portion of the incineration chamber (22), producing a line of small flames (59). Polluted air, passing downwardly through vertically suspended heat exchanger tubes (47) wholly within the combustion chamber, is preheated and then discharged downwardly against the flames 59 of the linear burner (50), producing products of combustion and air heated to about 1400.degree. F. The products of combustion and air pass upwardly and on opposite outer sides of the tubes (47) and exit the incinerator. The heated air and products of combustion heat the insulation sufficiently that it emits radiant energy inwardly for heating the tubes 47 by radiation, as the products of combustion and air heat the tubes 47 by convective heat transfer.

In the past, numerous incinerators have been devised in order to burn airborne organic matter entrained in air so as to convert the matter into essentially carbon dioxide and water vapor. Such incinerators have usually employed a preheater in the form of a heat exchanger provided with a plurality of tubes, through which the air and combustible matter passes, as these tubes are heated by the products of combustion being exhausted from the combustion chamber.
In the present day, more and more emphasis is being placed upon thoroughly incinerating all organic volatiles and other organic matter entrained in air, particularly the volatile organic compounds (VOC's) in air discharged from industrial plants. Such volatiles emanate from paint booths, drying ovens, and the like. In the past, such incinerators have usually been quite complex structures.
The concentration of VOC's contained in the atmosphere expelled from certain industrial processes, such as the exhaust from ovens used for curing various types of coatings, is usually much below a concentration required for producing a combustible mixture or even for the lower explosion limit (LEL).
Therefore, these VOC's have to be oxidized to harmless gases by incineration. They cannot be converted to products of combustion simply by being burned because of their low concentration in the mixture. However, when these compounds are exposed to an increased temperature for sufficient time in the presence of oxygen, they can be oxidized into harmless products of combustion. This process is usually accomplished at temperatures of between 1250.degree. F. and 1500.degree. F. and with dwell times for the organic matter from 0.2 seconds to 1 second.
In many applications where incineration of the VOC'S are required, the temperature of the mixture containing the VOC's is relatively low, 250.degree. F. to 350.degree. F. compared to the temperature required f or oxidation of the VOC's. Therefore, in order to conserve energy, most incinerators are of the recuperative type which allow for pre-heating the incoming mixture containing VOC's by the hot gases generated from the incineration process. Therefore, the energy added to accomplish the incineration can be greatly reduced if the incoming mixture can be separated from the combustion gases and pre-heated normally to about 1000.degree. F. If pre-heating can be accomplished to this temperature, then the energy added to the mixture to be incinerated is only that required to heat the mixture from 1000.degree. F. to the incineration temperature, which is usually in the range of 1250.degree. F. to 1500.degree. F.
In order to prewheat the incoming mixture containing the VOC's, some type of air-to-air heat exchanger is required. A typical heat exchanger used for this application would employ tubular heat transfer surfaces which could be constructed in many geometries. Most practical heat exchangers of this type use either cylindrical or rectangular tubular heat transfer surfaces.
In conventional incinerators employing pre-heating, it would not be desirable to mix the incoming polluted air mixture with the relatively clean air from the incineration process. Therefore, a gas tight seal is required to prevent the intermixing of the two. This gas tight seal is usually produced by welding the heat transfer tubular surfaces into headers. In many designs, the tube headers, in which the heat transfer tubes are welded, are exposed to the high exhaust gas temperatures of the incinerator. Failure of these welds and the heat exchangers associated with these types of incinerators have been a common problem in the past. Also, the failure of these heat exchangers has created expensive repairs.
A problem associated with the type of heat exchangers described above is that the resulting structure must provide for the expansion and contraction of the multiple tubes contained within one heat exchanger when different tubes are exposed to different temperatures. Carbide precipitation within the weld is another problem in prior art devices and in many instances, the weldment is subjected to high stresses as a result of the expansion and contraction of the heat transfer tubes.
Attempts have been made, in the past, to only weld one end of each heat transfer tube into one of the tube plates and allow the other end to float in the other tube plate. While this concept does provide for expansion and contraction of the tubes, it adds another design problem of providing a means to seal each tube while it expands and contracts within the tube plate. Thus, these types of incinerators have not been satisfactory or widely accepted because of leakage at the seal.
The present invention overcomes the difficulties prescribed above by providing an inexpensive and yet quite durable and efficient incinerator.
I have found that, to achieve virtually 100% destruction of VOC's, it is not necessary to provide a specific dwell time for the air and VOC mixture in the combustion chamber at a constant, specific, elevated temperature. In other words, the mixture of incoming air and VOC's does not have to be held at a specified constant temperature before it enters the primary heat exchanger. The rate at which the VOC's are oxidized depends upon, among other things, the temperature of the mixture. Thus, the dwell time required will depend upon the temperature versus time relationship experienced by the mixture as it passes through the combustion chamber.
In the preferred embodiment of this invention, the heat transfer to the incoming mixture occurs throughout the incineration chamber. This concept provides for more efficient heating of the incoming mixture while, at the same time, insuring that the time-temperature relationship, for essentially 100% destruction of the VOC's is maintained.

Method and apparatus for incinerating combustibles carried by an air stream


The present invention is directed to luminous drumsticks. The drumsticks of the present invention permit the drummer to perform visually dramatic drumstick maneuvers and exhibitions without impeding the drummer's traditional responsibility of providing a continuum of timely rhythm to the subject music. This is achieved because the drumsticks embodying this invention comprise drumstick body elements which are configured such that the center of mass of the drumstick is at substantially the midpoint of the length of the drumstick body, and such that either end of the drumstick may function as the drum tip. The ends are also configured such that they are compatible for universal use on all types of percussion instruments. Such a construction of drumsticks permits the drummer to predictably and confidently manipulate the drumsticks for the desired visual, yet timely rhythmic affect. The present invention also contemplates a novel method of manufacturing the same.

1. The Field of the Invention
The present invention is directed to drumsticks and methods for making the same. In particular, the drumsticks of the present invention have a construction which permits the insertion of radiant or reflective light sources. Furthermore, drumsticks of the present invention are constructed so as to be substantially symmetric in mass and configuration, and having a simplified construction.
2. Description of the Currently Available Products
Currently available luminous or lighted drumsticks offer the drummer the advantage of being not only heard, but also seen. Such luminous drumsticks include drumsticks that require some power source combined with a light source. For example, some luminous drumsticks include an electrical lead extending from the end of the drumstick which supplies the necessary power or energy to a light source or diode within or attached to the drumstick. Such drumsticks proffer the drummer an electrical light source within the specially configured tip of the drumstick tethered to an electrical lead.
Other luminous drumsticks similarly comprise a specially configured electrical light diode in one tip of the drumstick, but draw upon electrical power from a source such as an internal battery housed in the other end of the drumstick shank. Such drumsticks require specialized electrical and structural construction to assure an electrical circuit including a power source, light emitting diode, and leads between the power source and the light emitting diode.
Still other luminous drumsticks comprise hollow shanks which may be colored or radiate by way of an insertable inner core, and further comprise particularly configured and structured handles and tips.
The currently available luminous drumsticks do not, however, serve the needs of the drummer who incorporates exhibition-type drumstick maneuvers into his performance and who wishes to be seen as well as heard. Drummers who play with bands remain, even today, largely relegated to establishing and maintaining the heart-beat of the band through the pervading cadence of the drum beat, but are typically only "heard and not seen." However, many drummers wish to be seen and to be part of a dramatic as well as audio contribution. Therefore, it is important for the drummer's movement to be not only visible, but unhindered or unimpeded. Luminous drumsticks, if properly configured, provide the drummer the capability of nearly unlimited range of movement and continuity during the drummer's exhibition and musical contribution.
When employing currently available luminous drumsticks, however, the drummer must either be tethered to a power source or be acutely aware of the orientation of the drumstick to assure that the specially designed and shaped tip of the drumstick is used to strike the percussion instrument, and is not being clasped in the palm of the drummer. As a result, the drummer is constrained to position, maintain, and assure that the drumstick is always held in his hand in a certain manner conducive to drumming. In other words, the currently available luminous drumsticks are designed and constructed to have a handle and a tip, serving mutually exclusive objectives and purposes. The handle portion of the currently available drumsticks serve to offer the drummer a suitable grip interface while also serving as the housing for the power source of some luminous drumsticks. The tip on the other hand, is designed to offer the drummer the optimum hammer effect upon the intended percussion instrument. Unfortunately, such configurations do not serve the needs of the drummer who for dramatic effect and/or audience appeal twirls or gyrates the drumstick.
Exhibition drumming is incorporated into the musical score or is extemporaneously interjected into the rhythm of the music in such a manner that maintaining the rhythm of the music and executing the exhibition maneuvers should be integrated functions. This requires the drummer to have the capability of being able to immediately make the transition from dazzling maneuvers to rhythmic drumming. This transition is shackled by the requisite handle-tip configurations and orientation of the currently available luminous drumsticks.
Similarly, some drummers also wish to toss the drumstick upward in a spinning or twirling fashion, yet need to be able to immediately continue playing upon the reclasping or catching of the drumsticks. Currently available drumsticks require the drummer to deliberately orient the drumstick in the requisite handle-tip attitude after every stunt before again striking the percussion instrument.
Furthermore, the currently available art does not generally lend itself to the acrobatic type exhibition drumming performed by concert drummers. The drummer's dramatic contribution to the musical presentation depends upon the ability of the drummer to confidently twirl, whirl, or toss the drumsticks without losing control of them or dropping them.
Preferably, the mass of the drumsticks should be proportionately distributed so as not to impede the physics of the desired twirl, whirl, or toss. For optimal execution of such exhibition drumming, the mass of the drumstick should not be asymmetrically distributed over the length of the drumstick. In other words, an imbalanced or disproportionate distribution of the mass of the drumstick does not permit the drummer to assuredly twirl, whirl, or spiningly toss the drumsticks or to predict the action or path of the drumsticks. Instead, the drumsticks should be properly balanced so the drummer does not lose control of the drumstick, or drop it.
Many of the currently available luminous drumsticks are imbalanced. For example, weighty battery units opposing light weight electrical leads and light emitting diodes results in the imbalance of the drumstick. Similarly, if the handle of the drumstick is significantly different in shape and mass from other aspects of the drumstick such as the tip, the ability of the drummer to manipulate the drumstick in a showy manner is impeded.
In addition, many of the currently available drumsticks call for the distinct configuration of drumstick tips or heads for mutually exclusive use in conjunction with different percussion instruments. This does not permit the drummer to readily and immediately shift from one percussion instrument to a stunt and then readily and immediately shift to a different percussion instrument, if desired. The currently available drumsticks are so designed to structurally withstand the physical effects of the prolonged pounding and hammering of the drumsticks on a variety of materials comprising the various percussion instruments.
Similarly, the currently available luminous drumsticks require highly complex electrical and/or specialized molding construction. As a result, the drumsticks are costly and difficult to fabricate and manufacture.

Apparatus and methods of manufacturing luminous drumsticks