A method and a device for transferring signalling information in a TDMA based system. Temporal alignment of values for a retransmission number parameter (R) with the TDMA frame structure is determined on the basis of which a first radio packet to be sent in a number of first TDMA frames is encoded by using a certain first value for the parameter and a second radio packet to be sent in a number of second TDMA frames is encoded by using a certain second value for the parameter. The first and second radio packets are transmitted to the recipient that adheres to the same temporal alignment rules and can thus properly decode both the packets. The solution can be utilized especially in GERAN radio access network with FLO (Flexible Layer One) for transferring signalling information on half-rate channels.

Modern wireless communication systems such as GSM (Global System for mobile communications) and UMTS (Universal Mobile Telecommunications System) are capable of transferring various types of data over the air interface between the network elements such as a base station and a mobile station (MS). As the general demand for transfer capacity continuously rises due to e.g. new multimedia services coming available, new more efficient techniques have been developed in order to exploit the existing resources to a maximum extent.
A technical report [3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network: Flexible layer One (Rel 6)] discloses a concept of flexible layer one, a new physical layer proposed for the GERAN. The ingenuity of the concept relies on the fact that the configuration of the physical layer including e.g. channel coding and interleaving is specified not until the call set-up. Thus, the support of new services can be handled smoothly without having to specify new coding configuration schemes separately in connection with each release.
Development work of the FLO concept has been provided with somewhat strict requirements. FLO should, for example, support multiplexing of parallel data flows on to a basic physical subchannel and provide optimisation of spectral efficiency through the support of different interleaving depths, unequal error protection/detection, reduced channel coding rate granularity and support of different (8PSK, GMSK etc) modulations. Moreover, the solution shall be future proof and minimize the overhead introduced by the radio protocol stack.
According to the GERAN Release 5 the MAC sublayer (Layer 2 for FLO) handles the mapping between the logical channels (traffic or control) and the basic physical subchannels introduced in [3GPP TS 45.002 V6.5.0 Technical Specification Group GSM/EDGE, Radio Access Network: Multiplexing and multiple access on the radio path (Rel 6)].
In UTRAN (UMTS Radio Access Network), the MAC utilizes so-called Transport Channels TrCH for transferring data flows with given QoS's (Quality of Service) over the air interface. As a result, several transport channels, that are configured at call set-up, can be active at the same time and be multiplexed at the physical layer.
Now, by adopting the idea of FLO, aforesaid flexible transport channels can be utilized in GERAN as well. Accordingly, the physical layer of GERAN may offer one or several transport channels to the MAC sublayer. Each of these transport channels can carry one data flow providing a certain Quality of Service (QoS). A number of transport channels can be multiplexed and sent on the same basic physical subchannel at the same time.
The configuration of a transport channel i.e. the number of input bits, channel coding, interleaving etc. is denoted as a Transport Format (TF). Furthermore, a number of different transport formats can be associated to a single transport channel. The configuration of the transport formats is completely controlled by the RAN (Radio Access Network) and signalled to the MS at call set-up. Correct interpretation of the TF is crucial at the receiving end as well as the transport format defines the utilized configuration for decoding of the data. When configuring a transport format, the RAN can, for example, choose between a number of predefined CRC (Cyclic Redundancy Check) lengths and block lengths.
On transport channels, transport blocks (TB) are exchanged between the MAC sublayer and the physical layer on a transmission time interval (TTI) basis. For each TTI a transport format is chosen and indicated through the transport format indicator (TFIN). In other words, the TFIN tells which transport format to use for that particular transport block on that particular TrCH during that particular TTI. When a transport channel is inactive, the transport format with a transport block size of zero (empty transport format) is selected.
Only a limited number of combinations of the transport formats of the different transport channels are allowed. A valid combination is called a Transport Format Combination (TFC). The set of valid TFCs on a basic physical subchannel is called a Transport Format Combination Set (TFCS). The TFCS is signalled through Calculated Transport Format Combinations (CTFC).
In order to decode a received sequence the receiver needs to know the active TFC for the radio packet. This information is transmitted in the Transport Format Combination Identifier (TFCI) field. Aforesaid field is basically a layer 1 header and has the same function as the stealing bits in GSM. A unique TFCI value is assigned to each of the TFC within a TFCS and upon receipt of a radio packet it is the first element to be decoded by the receiver. By utilizing the decoded TFCI value the transport formats for the different transport channels can be determined and the actual decoding can start.
In case of multislot operation, there shall be one FLO instance for each basic physical subchannel. Each FLO instance is configured independently by Layer 3 and gets an own TFCS as a result. The number of allocated basic physical sub channels depends on the multislot capabilities of the MS.
For the time being the use of FLO is planned to be limited to dedicated channels only, thus maintaining the 26-multiframe structure for which the SACCH (Slow Associated Control Channel) shall be treated as a separate logical channel based on GERAN Release 5.
The concept of transport formats and channels as presented in 3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network; Flexible Layer One (Rel 6) is visualized in FIG. 1 where e.g. coded speech is to be transmitted over FLO. Speech is transferred by using three different modes MODE 1, MODE 2, MODE 3 with different bit rates and an additional comfort noise generation mode CNG MODE. Inside a mode the speech bits have been divided into three different classes represented by three transport channels TrCHA 102, TrCHB 104, and TrCHC 106 on the basis of their varying importance during the speech reconstruction stage, for example. Numbers inside the blocks, see e.g. the block pointed by legend 108, being arbitrary in this example though, indicate the required number of bits in a transport channel and codec mode specific manner. Hence, it can be noticed from the figure that TrCHA contains four transport formats (0, 60, 40, 30), TrCHB three transport formats (0, 20, 40) and TrCHC only two formats (0, 20). Resulting transport format combinations TFC1-TFC4, that refer to transport formats on different channels that can be active at the same time, are depicted with dotted lines in the figure. All these valid combinations constitute the TFCS that is signaled through CTFC. An example of CTFC determination is found in 3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network; Flexible layer One (Rel 6) in addition to techniques applicable in proper TFC selection.
A protocol architecture of FLO in case of Iu mode is depicted in FIG. 2 wherein MAC layer 208 maps either a plurality of logical channels or TBFs (temporary block flows) from RLC entities located in RLC layer 206, said RLC layer 206 receiving data from e.g. PDCP 204 (Packet Data Convergence Protocol) and controlled by RRC (Radio Resource Controller) 202, to physical layer 210. In current specification 3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network; Flexible Layer One (Rel 6) logical channels are used but are presumably to be replaced with the concept of temporary block flows in the future. TBF concept is described in reference 3GPP TS 44.160 V6.3.0 Technical Specification Group GSM/EDGE, General Packet Radio Service (GPRS); Mobile Station (MS) - Base Station System (BSS) interface; Radio Link Control/Medium Access Control (RLC/MAC) protocol lu mode (Rel 6) in more detail. A dedicated channel (DCH) can be used as a transport channel dedicated to one MS in uplink or downlink direction. Three different DCHs have been introduced: CDCH (Control-plane DCH), UDCH (User-plane DCH) and ADCH (Associated DCH), the CDCH and UDCH of which used for transmission of RLC/MAC data transfer blocks, whereas the ADCH targeted for transmission of RLC/MAC control blocks. A mobile station may concurrently have a plurality of transport channels active.
The FLO architecture is illustrated in FIG. 3 especially in relation to Layer 1 for FLO. In this version only a one-step interleaving has been assumed, i.e. all transport channels on one basic physical subchannel have the same interleaving depth. An alternative architecture with two-step interleaving is disclosed in 3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network; Flexible Layer One (Rel 6) for review. Basic error detection is carried out with a cyclic redundancy check. A Transport Block is inputted to error detection 302 that utilizes a selected generator polynomial in order to calculate the checksum to be attached to the block. Next, the updated block called Code Block is fed into a convolutional channel coder 304 introducing additional redundancy to it. In rate matching 306 bits of an Encoded Block are either repeated or punctured. As the block size can vary, also the number of bits on a transport channel may correspondingly fluctuate. Thereupon, bits shall be repeated or punctured in order to keep the overall bit rate in line with the actual allocated bit rate of the corresponding sub-channel. Output from rate matching block 306 is a called a Radio Frame. Transport channel multiplexing 308 takes care of multiplexing of Radio Frames from active transport channels TrCH(i) . . . TrCH(I) received from matching block 306 into a CCTrCH (Coded Composite Transport Channel). In TFCI mapping 310 a TFCI is constructed for the CCTrCH. The size of the TFCI depends on the number of TFCs needed. The size should be minimized in order to avoid unnecessary overhead over the air interface. For example, a TFCI of 3 bits can indicate 8 different transport format combinations. If these are not enough, a dynamic connection reconfiguration is needed to be performed. The TFCI is (block) coded and then interleaved 312 with CCTrCH (these two constituting a Radio Packet) on bursts. The selected interleaving technique is configured at call set-up
RRC layer, Layer 3 for FLO, manages set-up, reconfiguration and release of the traffic channels. Upon creating a new connection, Layer 3 indicates to the lower layers various parameters to configure the physical, MAC and RLC layers. Parameters include the transport channel identity (TrCH Id) and transport format set for each transport channel, transport format combination set through CTFC with modulation parameter etc. In addition, Layer 3 provides transport channel specific parameters such as CRC size, rate matching parameters, transport format dynamic attributes etc. The transport channels and the transport format combination set are separately configurable in the uplink and downlink directions by utilizing e.g. Radio Bearer procedures disclosed in sections 7.14.1 and 7.19 of 3GPP TS 44.118 V6.1.0 Technical Specification Group GSM/EDGE, Radio Access Network; Mobile radio interface layer 3 specification; Radio Resource Control (RRC) protocol lu Mode (Rel 6) in more detail.
Furthermore, Layer 3 may include information about transport format combination subset(s) to further restrict the use of transport format combinations within the TFCS. Such information may be formed via a "minimum allowed transport format combination index", an "allowed transport format combination list", a "non-allowed transport formation combination list" etc.
Clearly also incremental TFCS reconfiguration should be possible in FLO, i.e. information only about transport channels or TFCs that are added, modified or deleted could be signalled by e.g. modified Radio Bearer signalling. After various reconfigurations, the overall configuration should still be consistent, which could be assured by, for example, removing all TFCs from the TFCS that utilize a transport channel to be released.
In addition to mere payload data also signalling information is transferred by utilizing the FLO concept. The transmission of signalling data must be made especially secure as the error scenarios arising from partially corrupted or completely lost signalling messages may even corrupt the whole connection if necessary corrective actions are not taken. Thus both the control plane and RLC/MAC level control messages shall be transferred with sufficient protection; FLO concept for it's part enables flexible and dynamic allocation and tuning of transfer resources, therefore the protection for signalling may be changed and the signalling even be multiplexed with outer radio bearers. In GSM, CS1 coding has been traditionally used for the protection of signalling. Flexibility offered by the FLO shall, however, not be utilized in the case of control plane information transfer as it could lead to inconsistent performance throughout the network. Meanwhile, the transfer parameters for signalling information shall be kept fixed and in the case of full rate channels, the first TFC with TFCI=0 is allocated solely for signalling transfer with only one active transport channel with 184 bit transport blocks and 18 bit CRC.
In order to guarantee seamless handovers between full rate and half rate channels the link level performance of associated signalling must be similar for the two different channel usage modes. Accordingly, the coding rate of associated signalling on half rate (HR) channels must be equal to the coding rate of associated signalling on full rate (FR) channels. In GSM/EDGE the interleaving depth of FACCH (Fast Associated Control Channel) is increased on half rate channels: it's twice the interleaving depth of TCH/H. As a result the performance of FACCH/H is very similar to the performance of FACCH/F; see 3GPP TS 45.003 V6.2.0 Technical Specification Group GSM/EDGE, Radio Access Network; Channel coding (Rel 6).
However, with the one step interleaving architecture, all TrCHs on one basic physical subchannel have the same interleaving depth, and the MAC layer shall send the same transport block twice in a row instead of the above traditional solution. Since coded bits of the same transport block can be found in two consecutive radio packets, the effect is as if the interleaving depth was twice the interleaving used for one radio packet. Two TFCs are defined for sending signalling messages: one is used for the first transmission and the other for the second transmission. For the transport formats used on the transport channel for signalling, an additional dynamic transport format attribute is required for HR channels. Layer 3 configures the two TFCs such that, in rate matching, the attribute, parameter R, shall be equal to 0 for the first transmission (first radio packet) and equal to 1 for the retransmission (second radio packet); 3GPP TR 45.902 V6.4.0 Technical Specification Group GSM/EDGE, Radio Access Network; Flexible layer One (Rel 6) discloses further information about the rate matching algorithm. Therefore, two TFCIs with TFCI=0 and TFCI=1 are defined for signalling messages on HR channels, each corresponding to one of the two transport formats above. The receiver is able to determine whether it is a question about receiving the first or the second transmission of a signalling block (and therefore apply the appropriate decoding procedures) through the value of the TFCI. The aforesaid two TFCs shall be configured as in the case of full rate channels, but the transport formats shall have a different value of the retransmission number parameter R.
Regardless of the above somewhat feasible solution for providing consistent signalling transfer in different network scenarios and conditions, a number of problems arise especially during a handover between full rate and half rate channels. First, the old TFCS cannot be utilized as such and the TFCS reconfiguration process is an inevitable consequence thereof. Secondly, if the TFCS has been previously configured to reserve all the possible TFCs, i.e. the TFCI space is in full use, moving to an HR channel would require adding at least one more bit to the TFCI if possible, rejecting the handover request, or removing one user data TFC in order to provide an additional one for signalling purposes.

Method and a device for transferring signalling information in a TDMA based system


A voice codec apparatus for predictive coding is disclosed, in which an automatic gain control circuit controls the gain for decoding by the use of a maximum prediction value generated at the time of coding. The accurate gain control of the output signal is thus made possible at the time of decoding.

1. Field of the Invention
The present invention relates to a voice codec apparatus mounted in a telephone, an acoustic device or the like, or more in particular to a voice codec apparatus for performing predictive coding. In the present specification, the voice codec apparatus is defined as an apparatus including a coder for coding the voice signal and a decoder for decoding the coded voice signal.
2. Description of the Related Art
The voice codec apparatus is used in a speaker telephone and an audio apparatus or the like. The voice codec apparatus needs to control the gain of the decoded output signal in order to obtain an appropriate amplitude of an output voice signal. Conventionally, the gain control is made on the basis of the amplitude of a voice signal which is input to the voice codec apparatus. Hereinafter, the voice signal which is input to the voice codec apparatus is referred to as "the input voice signal".
As a method for making the gain control, there is a method in which the amplitude of the input voice signal is detected by an amplitude detection circuit and the gain is determined based on a maximum value of the detected amplitude. Such a method is disclosed in Japanese Laid-Open Publication No. 59-44684 entitled "Electronic Clock with Voice Storage Function". According to the description of the reference, the amplitude of the input voice signal is detected at the time of coding, a maximum value of the detected amplitude of the input voice signal is stored and the gain is controlled to an optimum value on the basis of the maximum value of the amplitude stored at the time of decoding.
According to a conventional gain control method described above, when an impulse noise having an amplitude larger than the maximum amplitude value of the input voice signal is superimposed on the input voice signal, the amplitude detection circuit incorrectly detects the amplitude of the impulse noise as the maximum value of the amplitude of the input voice signal. This is because the amplitude detection circuit cannot distinguish the impulse noise and the input voice signal. As a result, at the time of decoding, a gain determining circuit determines the gain on the basis of the maximum value which is different from the maximum amplitude value of the input voice signal. Thus, the conventional gain control method described above has a problem in that the gain determining circuit cannot control the gain accurately when an impulse noise having an amplitude larger than the maximum amplitude value of the input voice signal is superimposed on the input voice signal.
The problem mentioned above will be described below with reference to FIG. 3. FIG. 3 shows a waveform of the input voice signal and a maximum value of the input voice signal detected by the conventional amplitude detection circuit in the case where the impulse noise is superimposed on the input voice signal. As shown in FIG. 3, in the case where the impulse noise N is superimposed on the input voice signal S, the amplitude detection circuit for detecting the amplitude of the input voice signal detects the maximum value of amplitude of the impulse noise N as a maximum amplitude value Smax of the input voice signal S. The detected maximum value Smax is stored in memory. At the time of reproduction, a gain determining circuit reads the maximum value Smax stored in the memory, and the gain of the output signal is determined on the basis of the maximum value Smax. As a consequence, the gain thus determined is smaller than the gain in the absence of the impulse noise, which raises a problem in that the volume of the voice signal reproduced is smaller than that in the absence of the impulse noise.


An electric power controller for a vehicle with stop-start system is provided to prevent electric energy from being decreased in a power capacitor when an engine is in an idle-stop state. The engine is in the idle-stop state by idle-stop control means, the transfer of the electric energy between the power capacitor and a vehicle-mounted battery is stopped by power control means connected between the power capacitor and the vehicle-mounted battery.

1. Field of the Invention
The present invention relates to an electric power controller for a vehicle with stop-start system.
2. Description of the Background Art
In JP8-196006A, there is disclosed a retarder device for use in a general vehicle, while an electric power controller for a vehicle with stop-start system is not disclosed therein. In such the retarder device, a motor/generator is connected to an engine output shaft. A power capacitor for charging and discharging electric power and a vehicle-mounted battery for supplying electric power to an electric load are connected to the motor/generator. A DC/DC converter is connected between the power capacitor and the vehicle-mounted battery. The motor/generator is used as a generator when an engine is braked, and converts a mechanical energy of the engine into an electric energy and charges the power capacitor with the electric energy. Further, the motor/generator is operated as a motor when the engine is started, and directly drives a crank shaft of the engine using the electric energy charged in the power capacitor. The motor/generator is required to generate a high level of torque for directly driving the engine when the engine is started. In the power capacitor disclosed in JP8-196006A, a capacitor having a high voltage of 200V or more is used to meet this requirement.
In the retarder device in JP8-196006A, the DC/DC converter is driven when the engine is stopped to transfer electric power to the vehicle-mounted battery from the power capacitor. The power capacitor has a self-discharging characteristic in the state of being condensed. Accordingly, in order to prevent loss of the electric power energy due to the self-discharging, when the engine is stopped, the electric energy accumulated in the power capacitor is transferred to the vehicle-mounted battery by means of the DC/DC converter. When the engine is stopped, the electric power returns to the power capacitor from the vehicle-mounted battery by means of the DC/DC converter, and when the engine is started, the electric power is fed to the motor/generator from the power capacitor.
As described above, since the retarder device in the related art is configured so that the electric power of the power capacitor is transferred to the vehicle-mounted battery through the DC/DC converter at the time of the engine stop so as to suppress the self-discharging generated when the power capacitor is left unmanaged for a long time, and the electric power transferred to the vehicle-mounted battery is returned to the power capacitor when the engine is started, there is a problem in that the electric energy is decreased before and after the engine stop in consideration of the conversion efficiency of the DC/DC converter. For example, if the conversion efficiency of the DC/DC converter is set to 90%, the total electric energy after the engine starting is decreased to 81% of the electric energy before the engine stop.
Further, even if the retarder device in the related art is modified so that the electric power transferred to the vehicle-mounted battery is not returned to the power capacitor when the engine is started, there is a problem that electric voltage of the power capacitor is decreased in order to transfer the electric energy to the vehicle-mounted battery from the power capacitor when the engine is stopped.

Electric power controller for vehicle with stop start system


Example embodiments are directed to a receiver for reducing ISI of at least one data transmission channel and compensating for signal gain loss, and method thereof. A receiver may include a high pass filter and a Schmitt trigger controlled by a plurality of first control signals and a plurality of second control signals. The plurality of first control signals and the plurality of second control signals may be used to shift a first trigger voltage and a second trigger voltage of the Schmitt trigger. A method of reducing intersymbol interference and compensating for signal gain loss of a receiver connected to at least one data transmission channel is also provided.

1. Field
Example embodiments relate to an electronic circuit, for example, to a receiver for reducing intersymbol interference (ISI) of a data transmission channel and compensating for signal gain loss, and method thereof.
2. Description of the Related Art
As the operating speed of semiconductor chips increases, so too may data transfer rates. A data input/output rate may also increase due to restrictions on the number of pins in the semiconductor chip. ISI may cause the degradation of signal quality in nonlinear components of a data transmission channel.
FIG. 1 illustrates a circuit of an example conventional data transmission channel. Referring to FIG. 1, a signal A output from a transmitter 110 may be transmitted to a receiver 130 through a channel 120. The receiver 130 may include a comparator 132 which may compare a signal B, having passed through the channel 120, to a reference voltage Vref, and an amplifier 134 which may amplify the output signals of the comparator 132.
FIGS. 2A, 2B and 2C illustrate example waveforms of signals transmitted through the data transmission channel of FIG. 1. FIG. 2A illustrates an example signal A output from the transmitter 110 of FIG. 1. FIG. 2B illustrates an example signal B passed through the channel 120 of FIG. 1. FIG. 2C illustrates an example output signal CO of the amplifier 134 of FIG. 1. The output signal CO of the amplifier 134 may have an 'eye' characteristic as illustrated in FIG. 3. Referring to FIG. 3, two eyes may exist in the signal CO and jitter noise may be widely distributed between the two eyes. This jitter noise may be caused by ISI.
Jitter noise caused by ISI of a data transmission channel may be removed using a signal shaper circuit, as disclosed in U.S. Pat. No. 5,565,812. Referring to FIG. 4, the signal shaper circuit may include a high pass filter 221, which may include a switched capacitor to receive an input signal IN, a comparator 222, a capacitance 223 and a Schmitt trigger 224. The high pass filter 221 may include two similarly constructed gain stages A and B, with a nominal gain of about 10 and a time constant of about 50 sample periods. The second gain stage B may be followed by the comparator 222. The gain stages may have a balanced, fully-differential structure. This example architecture may improve power supply rejection and immunity to parasitic effects. Amplifiers may be designed in such a way that their common mode operating point may be stabilized. The comparator 222 may have a differential input provided by the gain stages A and B and a single-ended output, and may provide a first approximation of the incoming digital signal. The capacitance 223 may be added at the output of the comparator 222 in order to limit its high-frequency response. The Schmitt trigger 224 may restore signal logic levels. The combination of the comparator 222 and the Schmitt trigger 224 may reduce very fast noise spikes, which may otherwise be sampled and misinterpreted.
The signal shaper circuit illustrated in FIG. 4 may have the frequency response characteristics illustrated in FIG. 5. Referring to FIG. 5, to receive an input signal IN modulated at a specific frequency, noise of frequency bands other than the modulation frequency may be removed. Noise from lower frequency bands may be removed by controlling a cut-off frequency using the switched capacitor, and noise from higher frequency bands may be removed using the Schmitt trigger 224. That is, the signal shaper circuit illustrated in FIG. 4 may improve the signal-to-noise ratio (SNR) of a signal.
However, the characteristics of a data transmission channel may vary with frequency. The gain of a receiver, for example, the signal shaper circuit illustrated in FIG. 4, may vary with channel characteristics as illustrated in FIG. 6, and gain loss may depend on frequency. Accordingly, a receiver capable of reducing ISI of a data transmission channel and gain loss according to frequency may help mitigate several detrimental effects.

Receiver for reducing intersymbol interference of a channel and compensating for signal gain loss, and method thereof


The present invention is directed to a novel intaglio printing press and a method for intaglio print making using the intaglio printing press described herein. The present invention is comprised generally of two assemblies: a press bed assembly and a print head assembly. The print head assembly serves as a first class lever within a pair of surfaces of a press bed assembly that define runway. The runway structure of the press bed assembly confines the force applied to the print head assembly and translates that force into a pressure directed to the print paper covered and inked artwork. The print paper and inked artwork are positioned proximate to the lower surface and the print head portion of the print head assembly is situated between the artwork and the upper surface. The print head assembly comprises one or more lever handles, a compression roller and one or more track roller. The lever handle(s) provide a torque lever for receiving a manually exerted downward force and to provide a handle for moving the print head assembly along the runway, thereby making compression passes across the artwork. The track roller and compression roller are secured a predetermined distance from each other and within a housing that forces the compression roller against the print paper and inked artwork at the lower surface of the runway and simultaneously forces the track roller (or bearings) against the upper surface of the runway. Printmaking proceeds one pass at a time across the lateral extent of the print paper covered artwork.

1. Field of the Invention
The present invention relates generally to printing presses. More particularly, the present invention relates to a method for intaglio print making and an intaglio printing press used therein.
2. Description of Related Art
The term intaglio refers to a die used in printing that is incised so as to produce an image in relief. Generally, an intaglio printing die has incisions, depressions and recessed areas that are marked into a plate of copper, brass, iron, zinc, or even plastic or linoleum. Many different processes and techniques may be employed in making an artwork die from the substrate plate which are suitable for intaglio printing, but a discussion of these techniques is beyond the scope of this application.
The basic methods of intaglio printmaking have remained relatively unchanged for centuries. Once an image has been incised onto a plate, ink is spread on the plate and forces it into the recessed areas of the plate. The surface is wiped clean of ink, leaving only the ink in the recessed areas of the plate. The plate is then placed in a special press and the paper that will receive the intaglio print is registered, face down, on the plate. It should be mentioned that one characteristic of intaglio prints that make them so desirable is the plate mark received in the paper from the outline of the plate, so care is taken that the paper is registered correctly to the plate. Often the paper is dampened to make it receptive to the ink and more supple so that the paper can more easily be pressed into the incised marks (dampening the paper also enhances the print mark). One or more felt blankets are placed over the paper in preparation for the press. The press applies direct pressure to the felt, which compresses the felt, and more importantly, the paper into the inked relief of the image on the plate.
Two general designs of printing presses suitable for intaglio printmaking have been used; a screw-type press that compresses the entire surface of the artwork between two flat plates, and a cylinder-type press that applies rotational pressure on the artwork at a point between two larger cylinders and simultaneously feeds the artwork plate, paper and felt in the direction of rotation. The screw-type press design has been in continuous use since the fifteenth century. It is simple to operate, relatively easy to maintain and has relatively few wear parts to replace. One major drawback in the screw-type design is that because force is simultaneously applied over the entire surface area of the work surface, the working pressure is inversely proportional to the surface area of the workpiece. The larger the work surface, the lower the amount of pressure that can be generated from the force applied by the screw. As a practical matter, the performance of most screw-type designs drops off considerably over a few hundred square inches of surface area.
Cylinder-type intaglio printing presses do not suffer from this shortcoming because the pressure to the workpiece is applied along a line between two cylindrically shaped rollers. Essentially, the cylinder-type design applies pressure in only one direction along the work surface, rather than across the entire two-dimensional surface area of the work surface as in the screw-type device. Because the surface area between the contact points on the rollers is relatively small, the cylinder-type design enables the operator to focus a significant amount of surface pressure with a comparatively low force applied on the rollers. Therefore, the length of the roller can be increased to accommodate larger artwork without a substantial corresponding decrease in the working pressure common to the screw-type press design.


A combination back pack and seat combination including a molded one piece chair seat and backrest with one aspect (FIGS. 1-3) of the invention including foldable legs pivotally supported on the bottom of the chair seat and another aspect (FIGS. 4-6) of the invention including a single tubular chair support. In each aspect of the invention a pair of shoulder straps are secured to the backrest portion of the chair with each of the straps being constructed of a flexible cord material and provided with a protective cushioning covering to engage the shoulder of a person transporting the chair. In the single tubular chair support embodiment a foldable tree stand is also provided and includes a base platform supporting the chair seat and a first V-shaped segment to engage a tree trunk. A pair of pivotally connected arms extend from the base with a second V-shaped segment connected to the arms to also frictionally engage the opposite side of the tree trunk and provide support for the tree stand.

In the hunting of deer and other large game it is common practice for the hunter to employ a tree stand or other elevated structure to provide a wide field of view for approaching game. Some of the tree stands are simple and inexpensive, employing only some wooden planks, while others are constructed of metal or metal and wood combinations, and can be elaborate and expensive. Many of the tree stands are uncomfortable to the occupant when utilized for extended periods. Some commercially available trees stands, and some custom made stands, are constructed of metal parts that are heavy and difficult to transport to the site of use.
It is an object of the present invention to provide a combination back pack and tree stand chair that is comfortable to occupy, relatively lightweight in construction, and relatively simple to transport to the site of use.
Another object of the present invention is to provide a combination back pack and tree stand that is relatively simple in construction and provides a comfortable seat for the occupant hunter at the site of use.
An additional object of the present invention is a lightweight, inexpensive, combination back pack and seat for a sportsman.
Another object of the present invention is a back pack and portable chair for use alone or with a hunter's tree stand.


A method of calculating a blood pressure, includes: providing a non-invasive blood pressure measurement apparatus which includes a cuff being inflatable and deflatable and adapted to be fitted on a part of a living body and in which a plurality of calculation methods each of which has priority in accordance with a type of noise information are set; detecting, by the cuff, a signal waveform representing a change in an oscillation amplitude and a change in a cuff pressure; determining the type of the noise information contained in the detected signal waveform; deciding the blood pressure from at least one candidate value for the blood pressure, which is calculated by one of the calculation methods that has the priority with respect to the determined type of the noise information; and displaying the decided blood pressure.

The present invention relates to a blood pressure calculation method for a non-invasive blood pressure measurement apparatus that measures a blood pressure by means of an oscillometric method. More particularly, the present invention relates to a blood pressure for a non-invasive blood pressure measurement apparatus configured such that a cuff being inflatable and deflatable and being fitted on a part of a subject's living body detects a change in an oscillation amplitude generated from arterial pulsation and a change in a cuff pressure, that a plurality of calculation methods is prepared as a calculation method for calculating a blood pressure value, for example, when a noise is generated due to body motion of the subject or when arrythmia due to disorder is observed or an abnormal pulse wave is generated with IABP (intra-aortic balloon pumping), and that a type of the noise or the arrythmia contained in the detection signal is determined and the optimum blood pressure calculation method is selected for each of the determined types of the noise or the arrythmia, thereby calculating and displaying the optimum blood pressure value.
In the past, in a non-invasive blood pressure measurement apparatus that measures a blood pressure by means of an oscillometric method, since a pressure noise resulting from subject's body motion is greatly superposed on the pulse wave of a cuff pressure, a predetermined logic element monitors the pulse wave of the cuff pressure to determine the presence of the noise resulting from the body motion. The non-invasive blood pressure measurement apparatus is provided with a means for generating a measurement error when it is determined that the noise is present, a means for adding information that represents occurrence of the noise during measurement, a means for reducing the noise resulting from the body motion, and the like.
In the related art, an electronic manometer is proposed that can measure a blood pressure with high precision even when a subject is walking, exercising or involved in other activities (see JP-A-2002-224059). The electronic manometer disclosed in JP-A-2002-224 059 includes: (1) a means for per forming frequency analysis on a pulse wave and a noise and transforming time series data into frequency data; (2) a means for comparing the frequency data of the pulse wave with the frequency data of the noise to calculate the frequency of the pulse wave; (3) a means for eliminating frequency components other than the frequency component of the pulse wave from the frequency data of the pulse wave; and (4) a means for transforming the frequency data of the pulse wave having other frequency components of the pulse wave eliminated therefrom into time series data to restore the pulse wave. Then, the electronic manometer calculates a blood pressure based on the restored pulse wave.
According to the electronic manometer disclosed in JP-A-2002-224059 having such a configuration, as a means for detecting a noise resulting from subject's body motion, a velocity sensor, an acceleration sensor, a position sensor, a displacement sensor, an angle sensor, a direction sensor, and an inclination sensor are used. In this case, when a photoelectronic sensor, for example, detects a photoplethysmograph signal and a noise resulting from subject's body motion is not present in the pulse wave signal, only a frequency component of the photoplethysmograph is present in the power spectrum of the photoplethysmograph, and no characteristic spectrum is present in the power spectrum of an acceleration signal. However, when the noise resulting from subject's body motion is present in the pulse wave signal, both a frequency component of the photoplethysmograph and a frequency component of the body motion are present in the power spectrum of the photoplethysmograph, and a spectrum of the frequency component of the body motion is present in the power spectrum of the acceleration signal. Therefore, the frequency component of the photoplethysmograph can be extracted by comparing the power spectrum of the photoplethysmograph with the power spectrum of the acceleration signal. That is, it is possible to remove the noise resulting from the body motion or the like from a pulse wave and calculate an appropriate blood pressure value based on the pulse wave.
Moreover, as a method for eliminating a noise resulting from subject's body motion or the like, contained in a pulse wave propagation signal detected from the subject, there are known (1) a method that compares a amplitude value (amplitude value) or an interval of pulse waves before and after a pulse wave signal of a cuff pressure and eliminates a waveform determined as being a noise; (2) a method that calculates moving average values of a plurality of varying amplitudes of a pulse wave signal of a cuff pressure; and (3) a method that eliminates a noise from a pulse wave signal of a cuff pressure by means of a mathematical method such as filter bank, FFT, or wavelet (see JP-A-2002-224061 and JP-A-2001-095766).
However, in the related-art blood pressure measurement method or blood pressure calculation method, when detecting the noise resulting from the body motion or the like to measure or calculate the blood pressure value, elimination of the noise or the determination as to invalidate or eliminate the measurement or calculation is performed by using one of the method described above. Therefore, the related-art method may not be the optimum calculation method depending on patients in various states and conditions, and it is thus difficult to perform the blood pressure measurement or calculation in a quick and appropriate manner.

Blood pressure calculation method for non-invasive blood pressure measurement apparatus


An image forming apparatus includes an image forming unit, a belt position detection unit to detect a position of a transfer belt in a rotating shaft direction of a driving roller, and a roller driving unit to tilt a steering roller to control the position of the transfer belt in the rotating shaft direction of the driving roller. In addition, a storage unit stores a reference position of the steering roller and a reference position of the transfer belt, and a control unit controls a formation position of the latent image, in a rotation axis direction of each photosensitive member, formed on each of a plurality of photosensitive members by the image forming unit based on a position of the transfer belt, in the rotating shaft direction of the driving roller, with respect to a detected reference position of the transfer belt and a tilt amount of the steering roller controlled by the roller driving unit with respect to the reference position of the steering roller.

1. Field of the Invention
The present invention relates to an image forming apparatus represented by a copying machine, a printer, a printing press, or the like and, more particularly, to an image forming apparatus including an endless belt-shaped transfer belt facing a plurality of image carriers.
2. Description of the Related Art
Along with an increase in speed of image forming apparatuses, dominating arrangements employ a plurality of image carriers facing an endless belt-shaped transfer belt and parallelly execute the image forming processes of the respective colors. For example, toner images of the respective colors are transferred to a transfer belt that is an endless belt in a superimposed manner, and the superimposed toner images are at once transferred to a printing material. The endless belt loops over a plurality of rollers and is driven by these rollers. The endless belt shifts in a direction perpendicular to the moving direction due to the diametral accuracy of the rollers or the alignment accuracy between the rollers.
Japanese Patent Laid-Open No. 2002-287527 discloses an arrangement for controlling the belt shift by detecting a variation in the position of a belt end face and adjusting, in proportion to the detected variation, the tilt of an adjustment roller that is one of the rollers to loop the belt.
In the arrangement described in Japanese Patent Laid-Open No. 2002-287527, however, changing the tilt of the adjustment roller causes a variation in the main scanning direction, that is, the direction perpendicular to the direction in which the belt should move. This may lead to an increase in color misalignment.

Image forming apparatus including transfer belt


In one embodiment, the present invention relates to a method of forming a NAND type flash memory device, involving the steps of growing a first oxide layer over at least a portion of a substrate, the substrate including a core region and a periphery region, the core region including a flash memory cell area and a select gate area and the periphery region including a high voltage transistor area and low voltage transistor area; depositing a first doped amorphous silicon layer over at least a portion of the first oxide layer; depositing a dielectric layer over at least a portion of the first doped amorphous silicon layer; removing portions of the first oxide layer, the first doped amorphous silicon layer, and the dielectric layer in the select gate area of the core region and the high voltage transistor area and the low voltage transistor area the periphery region; growing a second oxide layer over at least a portion of the substrate in the select gate area of the core region and the high voltage transistor area and the low voltage transistor area the periphery region; removing portions of the second oxide layer in the select gate area of the core region and the low voltage transistor area the periphery region; growing a third oxide layer over at least a portion of the substrate in the select gate area of the core region and the low voltage transistor area of the periphery region; depositing a second doped amorphous silicon layer over at least a portion of the dielectric layer, the second oxide layer and the third oxide layer; and forming a flash memory cell in the flash memory cell area of the core region, a select gate transistor in the select gate area of the core region, a low voltage transistor in the low voltage transistor area of the periphery region, and a high voltage transistor in the high voltage transistor area of the periphery region.

Semiconductor devices typically include multiple individual components formed on or within a substrate. Such devices often comprise a high density section and a low density section. For example, as illustrated in prior art FIG. 1a, a memory device such as a flash memory 10 comprises one or more high density core regions 11 and a low density peripheral portion 12 on a single substrate 13. The high density core regions 11 typically consist of at least one M.times.N array of individually addressable, substantially identical floating-gate type memory cells and the low density peripheral portion 12 typically includes input/output (I/O) circuitry and circuitry for selectively addressing the individual cells (such as decoders for connecting the source, gate and drain of selected cells to predetermined voltages or impedances to effect designated operations of the cell such as programming, reading or erasing).
The memory cells within the core portion 11 are coupled together in a NAND-type circuit configuration, such as, for example, the configuration illustrated in prior art FIG. 1b. Each memory cell 14 has a drain 14a, a source 14b and a stacked gate 14c. A plurality of memory cells 14 connected together in series with a drain select transistor at one end and a source select transistor at the other end to form a NAND string as illustrated in prior art FIG. 1b. Each stacked gate 14c is coupled to a word line (WL0, WL1, . . . , WLn) while each drain of the drain select transistors are coupled to a bit line (BL0, BL1, . . . , BLn). Lastly, each source of the source select transistors are coupled to a common source line Vss. Using peripheral decoder and control circuitry, each memory cell 14 can be addressed for programming, reading or erasing functions.
Prior art FIG. 1c represents a fragmentary cross section diagram of a typical memory cell 14 in the core region 11 of prior art FIGS. 1a and 1b. Such a cell 14 typically includes the source 14b, the drain 14a and a channel 15 in a substrate or P-well 16; and the stacked gate structure 14c overlying the channel 15. The stacked gate 14c further includes a thin gate dielectric layer 17a (commonly referred to as the tunnel oxide) formed on the surface of the P-well 16. The stacked gate 14c also includes a polysilicon floating gate 17b which overlies the tunnel oxide 17a and an interpoly dielectric layer 17c overlies the floating gate 17b. The interpoly dielectric layer 17c is often a multilayer insulator such as an oxide-nitride-oxide (ONO) layer having two oxide layers sandwiching a nitride layer. Lastly, a polysilicon control gate 17d overlies the interpoly dielectric layer 17c. The control gates 17d of the respective cells 14 that are formed in a lateral row share a common word line (WL) associated with the row of cells (see, for example, prior art FIG. 1b). In addition, as highlighted above, the drain regions 14a of the respective cells in a vertical column are connected together by a conductive bit line (BL). The channel 15 of the cell 14 conducts current between the source 14b and the drain 14a in accordance with an electric field developed in the channel 15 by the stacked gate structure 14c.
The process for making such NAND type flash memory devices includes numerous individual processing steps. Each flash memory device must be fabricated in the same manner as other flash memory devices to provide consistent performance and reliability. Generally speaking, the fewer the number of processing steps, the easier it is to fabricate uniform flash memory devices.
For example, fabricating the select gate transistors and the flash memory cells in the core region of NAND type flash memory devices is complicated and involves numerous processing steps. Conventional fabrication techniques involve initially growing a select gate oxide over the entire core region or substrate, providing a tunnel oxide mask over the select gate areas, etching the exposed oxide, removing the tunnel oxide mask, cleaning the substrate, and growing a tunnel oxide layer. The process may further involve various inspection and evaluation steps after one or more of the numerous processing steps.
There are several concerns with such a process. For instance, there is a high defect density associated with using the tunnel oxide mask. A so-called Poly 1 contact is undesirably employed as a select gate interconnect. As a result, excessively high or low Poly 1 doping levels affect device performance (charge gain/loss problems). Residual oxides are common place, leading to diminished electrical properties.
In view of the aforementioned concerns and problems, there is a need for flash memory cells of improved quality and more efficient methods of making such memory cells.

Method of forming select gate to improve reliability and performance for NAND type flash memory devices


An improved process for the production of ultralow denier, high-strength polybenzimidazole filaments is provided. A solution of the polymer is extruded vertically downward through a plurality of extrusion orifices into a gaseous atmosphere before being passed through a liquid coagulation bath. During their passage from the extrusion orifices to the exit from the coagulation bath, the filaments are drawn at an initial draw ratio of approximately 2:1 to 50:1. After being passed through the coagulaton bath, the filaments are washed, dried, and heat drawn at a heat draw ratio of approximately 1.5:1 to 10:1. The resulting filaments, having a denier per filament of approximately 0.05 to 0.50 and a tenacity of at least 4 grams per denier, are collected.

Polybenzimidazole is a non-flammable polymer which may be formed into textile fibers characterized by outstanding thermal, physical, and chemical stability. Processing parameters are well established for the extrusion of polybenzimidazole solutions into fibrous materials. Polybenzimidazole fibrous materials heretofore produced for textile applications commonly have exhibited a denier per filament of approximately 1.5.
Commonly assigned U.S. Pat. No. 3,441,640 broadly discloses a wet spinning method for the production of polybenzimidazole filaments having a denier per filament of 0.1 to 50. However, extremely fine filaments are not easily produced on a reliable basis by wet spinning methods. The unavoidable currents formed in the liquid as the polymer is extruded into it can disrupt the filaments. Also, the filaments tend to sag due to the fact that the horizontally extruded material has a higher specific gravity than the liquid of the spin bath.
Dry spinning processes, in which the polymer solution is extruded vertically downward into a hot stream of dry gas, have also been disclosed for the production of polybenzimidazole filaments. However, with super-fine filaments, the vertical distances commonly employed in such processes (e.g., 5 to 8 meters) may be a controlling factor since the filaments may not have sufficient strength to maintain integrity all the way to the bottom.
A dry jet/wet spinning process was disclosed in commonly assigned U.S. Pat. No. 3,851,025. That patent relates to the production of hollow polybenzimidazole filaments which are useful for specialized reverse osmosis applications. The patented process does not produce the ultralow denier filaments which are the subject of the present invention.
It is an object of the present invention to provide an improved process for the stable production of high-strength ultralow denier polybenzimidazole filaments.
It is an object of the present invention to provide a commercially practicable on-line, continuous process for the production of ultralow denier polybenzimidazole filaments without diminution of the desired tensile properties.
These and other objects, as well as the scope, nature, and utilization of the process will be apparent from the following description and appended claims.

Process for producing high-strength, ultralow denier polybenzimidazole (PBI) filaments


The present invention relates to membranes including a barrier layer which includes a blend of one or more aliphatic thermoplastic urethanes and one or more polar and partially crystalline materials. Under multi-layered embodiments, the barrier layer is laminated to at least one other layer formed from thermoplastic urethane, wherein the membranes are characterized in that hydrogen bonds are formed between the first layer of thermoplastic urethane and the second layer from the blend of aliphatic thermoplastic urethane and a copolymer of ethylene and vinyl alcohol.

The present invention relates to barrier membranes and, more particularly, to barrier membranes which, under certain embodiments, serve to selectively control the diffusion of gases through the membrane. Additionally, under certain embodiments, the membrane not only selectively controls the diffusion of gases through the membrane, but also allows for the controlled diffusion of gases normally contained in the atmosphere.
For a further understanding of the scope of the present invention, reference can be made to U.S. patent application Ser. No. 08/299,287, entitled xe2x80x9cCushioning Device With Improved Flexible Barrier Membranexe2x80x9d which was filed on Aug. 31, 1994 and allowed; U.S. patent application Ser. No. 08/299,286 entitled xe2x80x9cLaminated Resilient Flexible Barrier Membranesxe2x80x9d which was filed on Aug. 31, 1994 and abandoned; and U.S. patent application Ser. No. 08/475,276, entitled xe2x80x9cBarrier Membranes Including A Barrier Layer Employing Polyester Polyolsxe2x80x9d which is commonly owned and was filed on Jun. 1, 1995 and abandoned; each of the aforementioned patent applications being expressly incorporated herein by reference.
Barrier membranes useful for containing fluids, including liquids and/or gases, in a controlled manner have been employed for years in a wide variety of products ranging from bladders useful in inflatable objects, such as vehicle tires and sporting goods for example; to accumulators used on heavy machinery; to cushioning devices useful in footwear. Regardless of the intended use, barrier membranes must generally be flexible, resistant to environmental degradation and exhibit excellent gas transmission controls. Often, however, materials which exhibit acceptable flexibility characteristics tend to have an unacceptably low level of resistance to gas permeation. In contrast, materials which exhibit an acceptable level of resistance to gas permeation tend to have an unacceptably low level of flexibility.
In an attempt to address the concerns of both flexibility and imperviousness to gases, U.S. Pat. No. 5,036,110 which issued Jun. 30, 1991, to Moreaux describes resilient membranes for fitting hydropneumatic accumulators. According to Moreaux ""110, the membrane disclosed consists of a film formed from a graft polymer which is the reaction product of an aromatic thermoplastic polyurethane with a copolymer of ethylene and vinyl alcohol (EVOH), with this film being sandwiched between layers of thermoplastic polyurethane to form a laminate. While Moreaux ""110 attempts to address the concerns in the art relating to flexibility and imperviousness to gases, a perceived drawback of Moreaux is that the film described is not processable utilizing conventional sheet extrusion techniques. Thus, the present invention is directed to barrier membranes which are flexible, have good resistance to gas transmission, and under certain embodiments are processable into laminates utilizing conventional sheet extrusion techniques which are highly resistant to delamination.
While it should be understood by those skilled in the art upon review of the following specification and claims that the barrier membranes of the present invention have a broad range of applications, including but not limited to bladders for inflatable objects such as footballs, basketballs, soccer balls and inner tubes; films for food packaging; as well as the production of fuel lines and fuel storage tanks to name a few, still other highly desirable applications include their use in forming accumulators which are operable under high pressure environments.
For convenience, but without limitation, the barrier membranes of the present invention will hereinafter generally be described in terms of either accumulators or in terms of still another highly desirable application, namely for cushioning devices used in footwear. In order to fully discuss the applicability of the barrier membranes in terms of cushioning devices for footwear, a description of footwear in general is believed to be necessary.
Footwear, or more precisely, shoes generally include two major categories of components namely, a shoe upper and the sole. The general purpose of the shoe upper is to snugly and comfortably enclose the foot. Ideally, the shoe upper should be made from an attractive, highly durable, yet comfortable material or combination of materials. The sole, which also can be made from one or more durable materials, is particularly designed to provide traction, protect the wearer""s feet and body during use which is consistent with the design of the shoe. The considerable forces generated during athletic activities require that the sole of an athletic shoe provide enhanced protection and shock absorption for the feet, ankles and legs of the wearer. For example, impacts which occur during running activities can generate forces of up to 2-3 times the body weight of an individual while certain other activities such as, for example, playing basketball have been known to generate forces of up to approximately 6-10 times an individual""s body weight. Accordingly, many shoes and, more particularly, many athletic shoes are now provided with some type of resilient, shock-absorbent material or shock-absorbent components to cushion the user during strenuous athletic activity. Such resilient, shock-absorbent materials or components have now commonly come to be referred to in the shoe manufacturing industry as the midsole.
It has therefore been a focus of the industry to seek midsole designs which achieve an effective impact response in which both adequate shock absorption and resiliency are appropriately taken into account. Such resilient, shock-absorbent materials or components could also be applied to the insole portion of the shoe, which is generally defined as the portion of the shoe upper directly underlining the plantar surface of the foot.
A particular focus in the shoe manufacturing industry has been to seek midsole or insert structure designs which are adapted to contain fluids, in either the liquid or gaseous state, or both. Examples of gas-filled structures which are utilized within the soles of shoes are shown in U.S. Pat. No. 1,900,867 entitled xe2x80x9cCushion for Footwearxe2x80x9d which issued Oct. 13, 1908, to Miller; U.S. Pat. No. 1,069,001 entitled xe2x80x9cCushioned Sole and Heel for Shoesxe2x80x9d which issued Jul. 29, 1913, to Guy; U.S. Pat. No. 1,304,915 entitled xe2x80x9cPneumatic Insolexe2x80x9d which issued May 27, 1919, to Spinney; U.S. Pat. No. 1,514,468 entitled xe2x80x9cArch Cushionxe2x80x9d which issued Nov. 4, 1924, to Schopf; U.S. Pat. No. 2,080,469 entitled xe2x80x9cPneumatic Foot Supportxe2x80x9d which issued May 18, 1937, to Gilbert; U.S. Pat. No. 2,645,865 entitled xe2x80x9cCushioning Insole for Shoesxe2x80x9d which issued Jul. 21, 1953, to Towne; U.S. Pat. No. 2,677,906 entitled xe2x80x9cCushioned Inner Sole for Shoes and Method of Making the Samexe2x80x9d which issued May 11, 1954, to Reed; U.S. Pat. No. 4,183,156 entitled xe2x80x9cInsole Construction for Articles of Footwearxe2x80x9d which issued Jan. 15, 1980, to Rudy; U.S. Pat. No. 4,219,945 entitled xe2x80x9cFootwearxe2x80x9d which issued Sep. 2, 1980, also to Rudy; U.S. Pat. No. 4,722,131 entitled xe2x80x9cAir Cushion Shoe Solexe2x80x9d which issued Feb. 2, 1988, to Huang; and U.S. Pat. No. 4,864,738 entitled xe2x80x9cSole Construction for Footwearxe2x80x9d which issued Sep. 12, 1989, to Horovitz. As will be recognized by those skilled in the art, such gas filled structures often referred to in the shoe manufacturing industry as xe2x80x9cbladdersxe2x80x9d typically fall into two broad categories, namely (1) xe2x80x9cpermanentlyxe2x80x9d inflated systems such as those disclosed in U.S. Pat. Nos. 4,183,156 and 4,219,945 and (2) pump and valve adjustable systems as exemplified by U.S. Pat. No. 4,722,131. By way of further example, athletic shoes of the type disclosed in U.S. Pat. No. 4,182,156 which include xe2x80x9cpermanentlyxe2x80x9d inflated bladders have been successfully sold under the trade mark xe2x80x9cAir Solexe2x80x9d and other trademarks by Nike, Inc. of Beaverton, Oreg. To date, millions of pairs of athletic shoes of this type have been sold in the United States and throughout the world.
The permanently inflated bladders are typically constructed under methods using a flexible thermoplastic material which is inflated with a large molecule, low solubility coefficient gas otherwise referred to in the industry as a xe2x80x9csuper gas,xe2x80x9d such as SF6. By way of example, U.S. Pat. No. 4,340,626 entitled xe2x80x9cDiffusion Pumping Apparatus Self-Inflating Devicexe2x80x9d which issued Jul. 20, 1982, to Rudy, which is expressly incorporated herein by reference, discloses a pair of elastomeric, selectively permeable sheets of film which are formed into a bladder and thereafter inflated with a gas or mixture of gases to a prescribed pressure which preferably is above atmospheric pressure. The gas or gases utilized ideally have a relatively low diffusion rate through the selectively permeable bladder to the exterior environment while gases such as nitrogen, oxygen and argon which are contained in the atmosphere and have a relatively high diffusion rate are able to penetrate the bladder. This produces an increase in the total pressure within the bladder, by the addition of the partial pressures of the nitrogen, oxygen and argon from the atmosphere to the partial pressures of the gas or gases contained initially injected into the bladder upon inflation. This concept of a relative one-way addition of gases to enhance the total pressure of the bladder is now known as xe2x80x9cdiffusion pumping.xe2x80x9d
Under the diffusion pumping system and depending upon the bladder material used and the choice of gas or gases contained therein, there is a period of time involved before a steady state of internal pressure is achieved. For example, oxygen tends to diffuse into the bladder rather quickly with the effect being an increase in the internal pressure of approximately 2.5 psi. In contrast, over the course of a number of weeks nitrogen gas will gradually diffuse into the bladder resulting in an increase of pressure to approximately 12.0 psi. The gradual increase in bladder pressure typically causes an increase in tension in the bladder skin, resulting in a volume increase due to stretching. This effect is commonly referred to in the industry as xe2x80x9ctensile relaxationxe2x80x9d or xe2x80x9ccreep.xe2x80x9d Thus, it is of significant importance which materials are chosen for the bladder and the choice of the captive gas mixture utilized to initially inflate the bladder to achieve a bladder which is essentially permanently inflated at a desired internal pressure and which maintains a desired internal pressure over an extended period of time.
With regard to the systems utilized within the shoe manufacturing industry prior to and shortly after the introduction of the Air Sole(trademark) athletic shoes, many of the midsole bladders consisted of a single layer gas barrier type films made from polyvinylidene chloride based materials such as Saran(copyright) (which is a registered trademark of the Dow Chemical Co.) and which by their nature are rigid plastics, having relatively poor flex fatigue, heat sealability and elasticity. Still further, bladder films made under techniques such as laminations and coatings which involve one or more barrier materials in combination with a flexible bladder material (such as various thermoplastics) can potentially present a wide variety of problems to solve. Such difficulties with composite constructions include layer separation, peeling, gas diffusion or capillary action at weld interfaces, low elongation which leads to wrinkling of the inflated product, cloudy appearing finished bladders, reduced puncture resistance and tear strength, resistance to formation via blow-molding and/or heat-sealing and R-F welding, high cost processing, and difficulty with foam encapsulation and adhesive bonding, among others.
Yet another issue with previously known bladders is the use of tie-layers or adhesives in preparing laminates. The use of such tie layers or adhesives generally prevent regrinding and recycling of any waste materials created during product formation back into an usable product, and thus, also contribute to high cost of manufacturing and relative waste. These and other short comings of the prior art are described in more extensive detail in U.S. Pat. Nos. 4,340,626; 4,936,029 and 5,042,176, all of which are hereby expressly incorporated by reference.
With the extensive commercial success of the products such as the Air Sole(trademark) shoes, consumers have been able to enjoy a product with a long service life, superior shock absorbency and resiliency, reasonable cost, and inflation stability, without having to resort to pumps and valves. Thus, in light of the significant commercial acceptance and success that has been achieved through the use of long life inflated gas filled bladders, it is highly desirable to develop advancements relating to such products. The goal then is to provide flexible, xe2x80x9cpermanentlyxe2x80x9d inflated, gas-filled shoe cushioning components which meet, and hopefully exceed, performance achieved by such products as the Air Sole(trademark) athletic shoes offered by Nike, Inc.
One key area of potential advancement stems from a recognition that captive gases other than the large molecule, low solubility coefficient xe2x80x9csuper gasesxe2x80x9d as described in the ""156, ""945 and ""738 patents utilized can be replaced with less costly and possibly more environmentally friendly gases. For example, U.S. Pat. Nos. 4,936,029 and 5,042,176 specifically discuss the methods of producing a flexible bladder film that essentially maintains permanent inflation through the use of nitrogen as the captive gas. As further described in U.S. Pat. No. 4,906,502, also specifically incorporated herein by reference, many of the perceived problems discussed in the ""029 and ""176 patents are solved by the incorporation of mechanical barriers of crystalline material into the flexible film such as fabrics, filaments, scrims and meshes. Again, significant commercial success for footwear products using the technology described in ""502 patent under the trademark Tensile Airs(trademark) sold by Nike, Inc. has been achieved. The bladders utilized therein are typically comprised of a thermoplastic urethane laminated to a core fabric three-dimensional, double bar Raschel knit nylon fabric, having SF6 as the captive gas contained therein.
By way of example, an accepted method of measuring the relative permeance, permeability and diffusion of different film materials is set forth in the procedure designated as ASTM D-1434-82. According to ASTM D-1434-82, permeance, permeability and diffusion are measured by the following formulas:       Permeance              xe2x80x83                          (                  quantity                                xe2x80x83                              of                                xe2x80x83                              gas                )                              (          area          )                xc3x97                  (          time          )                xc3x97                  (                      press            .                          xe2x80x83                                    diff            .                    )                      =                  Permeance                              (            GTR            )                    /                      (                          press              .                              xe2x80x83                                          diff                        )                              =                        cc          .                                      (                          sq              .                              xe2x80x83                                          m                        )                                          (                          24                                            xe2x80x83                                          hr                        )                                          (            Pa            )                                    Permeability              xe2x80x83                                    (                      quantity                                      xe2x80x83                                    of                                      xe2x80x83                                    gas                    )                xc3x97                  (                      film                                      xe2x80x83                                    thick                    )                                      (          area          )                xc3x97                  (          time          )                xc3x97                  (                      press            .                          xe2x80x83                                    diff            .                    )                      =                  Permeability                              (            GTR            )                    xc3x97                                    (                              film                                                  xe2x80x83                                                thick                            )                        /                          (                              press                .                                  xe2x80x83                                                diff                            )                                          =                                    (            cc            )                                          (            mil            )                                                (                          sq              .                              xe2x80x83                                          m                        )                                          (                          24                                            xe2x80x83                                          hr                        )                                          (            Pa            )                                    Diffusion              xe2x80x83                          (                  quantity                                xe2x80x83                              of                                xe2x80x83                              gas                )                              (          area          )                xc3x97                  (          time          )                      =                            Gas                                xe2x80x83                              Transmission                                xe2x80x83                              Rate                          (          GTR          )                    =              cc                              (                          sq              .                              xe2x80x83                                          m                        )                                          (                          24                                            xe2x80x83                                          hr                        )
By utilizing the above listed formulas, the gas transmission rate in combination with a constant pressure differential and the film""s thickness, can be utilized to define the movement of gas under specific conditions. In this regard, the preferred gas transmission rate (GTR) for a bladder in an athletic shoe component which seeks to meet the rigorous demands of fatigue resistance imposed by heavy and repeated impacts has a gas transmission rate (GTR) value of approximately 10.0 or lower and, even more preferably, a (GTR) value of 2.0 or lower, for bladders having an average thickness of approximately 20 mils.
In addition to the aforementioned, the ""029 and ""176 patents also discuss problems encountered with previous attempts to use co-laminated combinations of plastic material which operate as barriers to oxygen. In this regard, the principal concern was the lack of fatigue resistance of the barrier layer. As described in the ""176 patent, a satisfactory co-lamination of polyvinylidene chloride (such as Saran(copyright)) and a urethane elastomer would require an intermediate bonding agent. Under such a construction, relatively complicated and expensive processing controls such as strict time-temperature relationships and the use of heated platens and pressures, coupled with a cold press to freeze the materials together under pressure would be required. Additionally, using adhesive tie layers or incorporating crystalline components into the flexible film at high enough levels to accomplish a gas transmission rate of 10.0 or less, reduces the flexibility of the film.
Cushioning devices which specifically eliminate adhesive tie layers have been known to separate or de-laminate especially along seams and edges. Thus, it has been a relatively recent focus of the industry to develop cushioning devices which reduce or eliminate the occurrence of delamination, ideally without the use of a xe2x80x9ctie layer.xe2x80x9d In this regard, the cushioning devices disclosed in co-pending U.S. application Ser. Nos. 08/299,286 and 08/299,287 eliminate adhesives tie layers by providing membranes including a first layer of thermoplastic urethane and a second layer including a copolymer of ethylene and vinyl alcohol wherein hydrogen bonding occurs over a segment of the membranes between the first and second layers. While the cushioning devices disclosed in U.S. patent application Ser. No. 08/299,287 and the laminated flexible barrier membranes of U.S. patent application Ser. No. 08/299,286 are believed to offer a significant improvement in the art, still further improvements are offered according to the teachings of the present invention.
It is therefore, a principal object of the present invention to provide barrier membranes which offer enhanced flexibility, durability and resistance to the undesired transmission of fluids therethrough.
It is another object of the present invention to provide barrier membranes which can essentially be permanently inflated with nitrogen or another environmentally desirable gas or combination of gases wherein the barrier membrane provides for a gas transmission rate value of 10.0 or less, based on a 20 mils average thickness.
It is still another object of the present invention to provide barrier membranes and, particularly those employed as cushioning devices with improved clarity and consistency.
It is yet another object of the present invention to provide barrier membranes which can be formed into laminated objects such as cushioning devices or accumulators which resist delamination and do not require a tie layer between the barrier layer and the flexible layers.
It is yet another object of the present invention to provide barrier layers which are reprocessable.
It is a further object of the present invention to provide barrier membranes which are formable utilizing the various techniques including, but not limited to, blow-molding, tubing, sheet extrusion, vacuum-forming, heat-sealing and RF welding.
Still another object of the present invention is to provide barrier membranes which prevent gas from escaping along interfaces between the layers in laminated embodiments and particularly along seems via capillary action.
It is yet another object of the present invention to provide a barrier membrane which allows for normal footwear processing such as encapsulation within a formable material.
While the aforementioned objects provide guidance as to possible applications for the barrier membranes of the present invention, it should be recognized by those skilled in the art that the recited objects are not intended to be exhaustive or limiting.
To achieve the foregoing objects, the present invention provides barrier membranes which have (1) a desirable level of flexibility (or rigidity); (2) a desirable level of resistance to degradation caused by moisture; (3) an acceptable level of imperviousness to fluids which can be in the form of gases, liquids or both depending mainly on the intended use of the product; and (4) are highly resistant to delamination when employed in a multi-layer structure. Regardless of the barrier membrane embodiment, each barrier membrane in accordance with the teachings of the present invention includes a barrier layer comprised at least in part of a blend of at least one aliphatic thermoplastic urethane and at least one copolymer of ethylene and vinyl alcohol.
The aliphatic thermoplastic urethanes employed, if not commercially available, are generally formed as the reaction product of (a) at least one polyester and/or polyether diol; (b) at least one difunctional extender, and (c) at least one aliphatic isocyanate and/or diisocyanate, as will be described in greater detail below. Additionally, it may be desirable to utilize a catalyst to activate the reaction and one or more processing aids.
The term xe2x80x9cthermoplasticxe2x80x9d as used herein is intended to mean that the material is capable of being softened by heating and hardened by cooling through a characteristic temperature range, and as such in the softened state can be shaped into various articles under various techniques.
The term xe2x80x9cpolyester diolxe2x80x9d as used herein is intended to preferably mean polymeric polyester diols having a molecular weight (determined by the ASTM D-4274 method) falling in the range of about 300 to about 4,000; more preferably from about 400 to about 2,000; and still more preferably between about 500 to about 1,500.
The term xe2x80x9cpolyether diolxe2x80x9d as used herein is intended to preferably mean polymeric polyether diols having a molecular weight (determined by ASTM D-4274 method) falling in the range of about 300 to about 6,500; more preferably from about 400 to about 4,500; and still more preferably between about 500 to about 3,000.
The term xe2x80x9cdifunctional extenderxe2x80x9d is used preferably in the commonly accepted sense to one skilled in the art and includes glycols, diamines, amino alcohols and the like having a molecular weight generally falling in the range of from about 60 to about 300.
The terms xe2x80x9caliphatic isocyanatexe2x80x9d and xe2x80x9caliphatic diisocyanatexe2x80x9d as used herein are intended preferably to mean linear aliphatic, cycloaliphatic and hindered aromatic isocyanates and diisocyanates where the isocyanate xe2x80x94Nxe2x80x94 is separated from the benzenoid ring proper by at least one carbon, and hence, acts to produce light stable or xe2x80x9caliphaticxe2x80x9d (poly)urethanes.
Ideally, the flexible barrier materials utilized in accordance with the teachings of the present invention should be capable of containing a captive gas for a relatively long period of time. In a highly preferred embodiment, for example, the barrier membrane should not lose more than about 20% of the initial inflated gas pressure over a period of two years. In other words, products inflated initially to a steady state pressure of between 20.0 to 22.0 psi should retain pressure in the range of about 16.0 to 18.0 psi.
Additionally, the barrier materials utilized should be flexible, relatively soft and compliant and should be highly resistant to fatigue and be capable of being welded to to form effective seals typically achieved by RF welding or heat sealing. The barrier material should also have the ability to withstand high cycle loads without failure, especially when the barrier material utilized has a thickness of between about 5 mils to about 50 mils. Another important characteristic of the barrier membrane is that they should be processable into various shapes by techniques used in high volume production. Among these techniques known in the art are extrusion, blow molding, injection molding, vacuum molding, rotary molding, transfer molding and pressure forming. The barrier membranes of the present invention should be preferably formable by extrusion techniques, such as tubing or sheet extrusion, including extrusion blow molding particularly at sufficiently high temperatures to attain the desired xe2x80x9cadhesivexe2x80x9d or xe2x80x9cchemicalxe2x80x9d bonding as will be described in greater detail below. These aforementioned processes should give rise to products whose cross-sectional dimensions can be varied.
As alluded to above, a significant feature of the barrier membranes of the present invention is the ability under embodiments formed into products intended to be inflated (such as cushioning devices for footwear) to control diffusion of mobile gases through the membrane and to retain the captive gases contained therein. By the present invention, not only are super gases usable as captive gases, but nitrogen gas may also be used as a captive gas due to the performance of the barrier. The practical effect of providing a barrier membrane for which nitrogen gas is a captive gas is significant in terms of protection of the earth""s ozone and global warming.
Under the present invention, if the barrier membrane is formed into a product such as a cushioning device, the membrane may be initially inflated with nitrogen gas or a mixture of nitrogen gas and one or more super gases or with air. If filled with nitrogen or a mixture of nitrogen and one or more super gases, an increment of pressure increase results from the relatively rapid diffusion of oxygen gas into the membrane, since the captive gas is essentially retained within the membrane. This effectively amounts to an increase in pressure of not greater than about 2.5 psi over the initial inflation pressure and results in a relatively modest volume growth of the membrane of between 1 to 5%, depending on the initial pressure. However, if air is used as the inflatant gas, oxygen tends to diffuse out of the membrane while the nitrogen is retained as the captive gas. In this instance, the diffusion of oxygen out of the membrane and the retention of the captive gas results in an incremental decrease of the steady state pressure over the initial inflation pressure.
A further feature of the present invention is the enhanced bonding which occurs between contiguous layers, thus, eliminating the need for adhesive tie layers. This is generally accomplished by laminating the first and second layers together using conventional techniques and thus, the laminated barrier membranes of the present invention are characterized in that significant hydrogen bonding occurs between a first layer formed from a blend of at least one aliphatic thermoplastic urethane and a copolymer of ethylene and vinyl alcohol, and a second layer of thermoplastic urethane. In addition to the occurrence of hydrogen bonding, it is theorized that there will also generally be a certain amount of covalent bonding between the first and second layers, especially when lesser amounts of the copolymer of ethylene and vinyl alcohol is used in the first layer and the thermoplastic urethanes of both the first and second layers have similar functionalities.
This invention has many other advantages which will be more apparent from consideration of the various forms and embodiments of the present invention. Again, while the embodiments shown in the accompanying drawings which form a part of the present specification are illustrative of embodiments employing the barrier membranes of the present invention, it should be clear that the barrier membranes have extensive application possibilities. Various exemplary embodiments will now be described in greater detail for the purpose of illustrating the general principles of the invention, without considering the following detailed description in the limiting sense.

Barrier membranes including a barrier layer employing aliphatic thermoplastic urethanes


Provided herein are systems, methods and devices for performing one or more titrations for oral appliance therapy. For example, a method for evaluating an outcome of oral appliance therapy in a subject is discussed herein. The method can include positioning an adjustable mandibular displacement device in an oral cavity of a subject and implementing an automatic titration protocol. The protocol can include controlling a protrusion level of the adjustable mandibular displacement device during a test period, monitoring physiological information from the subject during the test period, and analyzing the physiological information to evaluate the outcome of oral appliance therapy.

Obstructive sleep apnea (OSA) is a common disease that is largely under-diagnosed and untreated. Nasal continuous positive airway pressure (CPAP) is the standard treatment for OSA. CPAP entails use of a nose mask to deliver positive pressure, which dilates a subject's pharynx and eliminates obstruction. This therapy is highly efficacious and benign but is associated with low adherence in many subjects, particularly those with disease of mild and moderate severity. The principal alternative to CPAP therapy is oral appliance (OA) therapy in which a custom made mandibular repositioner (MR) is used to protrude the subject's mandible during sleep, thereby opening the subject's pharyngeal airway. OA therapy, while preferred and well accepted by most subjects, is not uniformly effective in eliminating sleep apnea.
The effectiveness of OA therapy can be improved by screening OSA subjects and prospectively identifying those suitable for this therapy. Studies of the passive pharynx indicate that the response of the pharynx to mandibular protrusion is dose dependent. In other words, incremental mandibular protrusion produces corresponding pharyngeal enlargement. However, clinical experience shows that excessive mandibular protrusion is undesirable, producing side effects, such as, pain and tooth movement that lead to discontinuation of therapy. In some cases, over-protrusion can worsen OSA. According to current practice, a treatment provider such as a dentist progressively protrudes the subject's mandible until a symptomatic response occurs. The subject is then reassessed to determine if OSA has resolved.
Prospective identification of suitable candidates, as well as target effective protrusion levels, can greatly facilitate treatment of OSA with OA therapy. U.S. Pat. No. 5,826,579 to Remmers et al., entitled "Remote-Controlled Mandibular Positioning Device and Method of Using the Device," which is incorporated herein in its entirety by reference, describes a remotely-controlled mandibular positioner (RCMP). Additionally, U.S. Pat. No. 6,273,859 to Remmers et al., entitled "Adaptively Controlled Mandibular Positioning Device and Method of Using the Device," which is incorporated herein in its entirety by reference, describes an OA therapy which is an automatically-controlled mandibular positioner (ACMP).
Conventionally, the overall approach to the titration for OA therapy is to evaluate the physiological response (e.g., respiratory events such as apneas, hypopneas, snoring etc. and/or evidence of obstructions) at discrete levels mandibular protrusion. For example, the level of protrusion is maintained constant all night and therapeutic effectiveness can be assessed offline at the end of the night (e.g., using conventional home monitors). Alternatively, therapeutic effectiveness is assessed offline by evaluating the physiologic response at various levels of protrusion that are collected during a polysomnographic study during which a technician either manually (e.g., at the MR) or remotely (e.g., using the RCMP) adjusts an MR. In addition, when providing OA therapy, the level of protrusion can be held at the level of protrusion determined to be therapeutically effective, or it can be automatically adjusted in response to evidence of obstruction (e.g., using the ACMP).

Systems and methods for providing an automated titration for oral appliance therapy


A display screen changeover apparatus changes a screen display when displaying HTML contents on a display screen of a television receiver. A contents analysis part analyzes display setting information with respect to the television receiver based on address information given to the HTML contents. A display setting part sets a display of the HTML contents with respect to the display screen based on a result of analysis obtained by the contents analysis part.

1. Field of the Invention
The present invention relates to a display screen changeover technique to quickly and easily perform a changeover of content display on a TV screen.
2. Description of the Related Art
Conventionally, there is a television receiver (hereinafter, referred to as TV) that receives broadcast signals transmitted via radio frequencies by an antenna or the like, and provides to viewing audience a preferred program selected by a tuner by displaying the program on a screen. A conventional TV displays a screen according to a format specified by a standard definition television (SDTV) or a format specified by a high definition television (HDTV). Here, the aspect ratio used in SDTV is different from the aspect ratio used in HDTV. Japanese Laid-Open Patent Applications No. 2004-186803 and No. 2007-60676 discloses a technique to convert a program according to an aspect ratio contained in broadcast signals into a program according to a previously set aspect ratio used in a display screen, and display the converted program on a display screen.
In recent years, in order to provide to viewing audience various kinds of information such as program related information, whether information, news information, etc., together with broadcast programs, there is provided data broadcast service such as cable television broadcast, digital broadcast, Internet protocol (IP) broadcast, etc. In this case, for example, signals sent from the above-mentioned various kinds of broadcast are converted into viewable data to be displayed on a TV screen. It should be noted that STB is provided with functions of demodulating or decoding each broadcast data, cancelling scramble, controlling limited reception, displaying electronic program guide (EPG), etc.
Furthermore, the conventional STB has a function of displaying on a TV screen a hyper text markup language (HTML) content such as a Web page (HTML page) acquired from an external server through, for example, the Internet.
According to the service using HTML contents, such as a HTML page supposing TV display, the aspect ratio of the HTML page is set to 4:3 (SD) or 16:9 (HD) so that HTML page can be displayed without scrolling by the display terminal.
It is usual for the service to display HTML pages on a TV to fix the size of the HTML page to an SD size or an HD size. Therefore, the display terminal merely has one browser display corresponding to either the SD size or the HD size.
However, in the service using both the HTML page of HD size and the HTML page of SD size, if a display is made with the fixed browser size, various problems may occur. For example, if an HTML page of SD size is displayed on the browser of HD size, the HTML page is displayed by left-aligned. Additionally, if a browser of HD size is displayed on 4:3 TV, it becomes a letter box display.
Because the HTML page of SD size is displayed in this letter box display, the HTML page displayed becomes small with respect to an area displayed by the TV. Moreover, if an HTML page of HD size is displayed on the browser of SD size, the entire HTML page does not fall within a display area of the browser, and it is necessary to scroll the screen when viewing the HTML page.
With such a service, it is assumed that a general HTML page is used other than that specified in the service. However, in a general site, because a page structure is not set in consideration with TV's over-scanning, the browser display may run off a TV display frame, which may result in that a part of the page cannot be displayed. Accordingly, in many cases, even if it is over-scanned on the TV side, a display is made by scaling the size to be smaller than an actual size so that the entire page can be displayed.
Moreover, when displaying on a TV screen, a display according to a format which a contents provider side desires to display cannot be displayed because the display is made in a state where a user previously sets by STB or the like.

Display screen changeover apparatus, display screen changeover method, display screen changeover program and computer readable recording medium storing a display screen changeover program