Abstract: An image forming apparatus suitable for use in a laser beam printer includes an image forming unit for forming an image on a photoconductor, and a reproduction unit for reproducing a high density image and a halftone image on the photoconductor. A detector then detects the density of the high density image and the halftone image formed on the photoconductor. A controller controls an image forming condition of the image forming unit based on a detection result by the detector.

Abstract: A membrane for the separation of carbon dioxide is disclosed which includes a hydrogel film of a cross-linked, vinyl alcohol/acrylic acid salt copolymer impregnated with an aqueous carrier solution containing a carbon dioxide carrier dissolved therein. A composition containing a solvent, an alkali metal carbonate or bicarbonates, and a polydentate ligand capable of forming a complex with an alkali metal ion is suitably used as the carrier solution. This composition may also be used for the preparation of a liquid film of a carbon dioxide separation membrane.

Abstract: In a modem pooling system for enabling selective connection of a plurality of data terminal units 5.sub.1 to 5.sub.n to a modem 9, each of the data terminal units 5.sub.1 to 5.sub.n is detected as to whether active or inactive; one data terminal (e.g. 5.sub.1) is selected as a responsive terminal unit from among the data terminal units determined to be active in accordance with a predetermined priority order; and the modem 9 is connected to the selected responsive terminal unit (e.g. 5.sub.1), prior to an incoming call response of the modem 9.

Abstract: This image processing apparatus inputs multi-valued image data, generates first recording data based on the input data, adds together several of the multi-valued image data, generates second recording data based on the added data and selects either the first or the second recording data. The image processing apparatus selects the first recording data in areas corresponding to the several multi-valued image data when preset data are included in those multi-valued image data, and selects the second recording data in areas corresponding to the several multi-valued image data when preset data are not included in those multi-valued image data.

Abstract: In a key telephone system in which a plurality of data terminals 371 . . . 37n such as personal computers are connected to a key service unit 1 connected to a plurality of telephone lines 251 . . . 25m, a modem 43 is pooled so as to be usable in common for the plural data terminals 371 . . . 37n. In response to a called party number signal from the Telephone line (e.g. 251), the key service unit 1 selects a single data terminal among the data terminals 371 . . . 37n now being in standby status, and closes a communication channel between the selected data terminal (e g 371) and the modem 43, so that a status equivalent to that where the selected data terminal 371 and the modem 43 are directly connected to each other can be established. Thereafter, the key service unit 1 indicates a called party number signal reception to the modem 43, and the modem 43 transmits a call to the selected data terminal 371.

Abstract: In a key telephone system in which a plurality of data terminals 37l . . . 37n such as personal computers are connected to a key service unit 1 connected to a plurality of telephone lines 25l . . . 25m, a modem 43 is pooled so as to be usable in common for the plural data terminals 37l . . . 37n. In response to a called party number signal from the telephone lines (e.g. 25l) in dial-in service, the key service unit 1 selects a single data terminal designated by an extension telephone designation signal in dial-in service from among the data terminals 37l . . . 37n, and closes a communication channel between the selected data terminal (e.g. 37l) and the modem 43, so that a status equivalent to that where the selected data terminal 37l and the modem 43 are directly connected to each other can be established. Thereafter, the key service unit 1 indicates a called party number signal reception to the modem 43, and the modem 43 transmits a call to the selected data terminal 37l.

Abstract: In a key telephone system in which a plurality of data terminals 37l . . . 37n such as personal computers are connected to a key service unit 1 connected to a plurality of ISDNs 23l . . . 23m, a terminal adapter (TA) 41 is pooled so as to be usable in common for the plural data terminals 37l . . . 37n. In response to a setup signal from an ISDN (e.g. 23l), the key service unit 1 selects a single data terminal designated by a subaddress included in the setup signal from among the data terminals 37l . . . 37n, and closes a communication channel between the selected data terminal (e.g. 37l) and the TA 41, so that a status equivalent to that where the selected data terminal 37l and the TA 41 are directly connected to each other can be established. Thereafter, the key service unit 1 transmits a setup signal to the TA 41, and the TA 41 transmits a call to the selected data terminal 37l.

Abstract: A surgical suture and a process for producing the same are disclosed, which surgical suture comprising a porous body of polytetrafluoroethylene having an outer circumference that is substantially free of pores, with only the interior being made porous.

Abstract: A porous material of polytetrafluoroethylene consisting essentially of fibers of polytetrafluoroethylene. The porous material of PTFE is produced by heat-treating a molded article prepared by paste extruding of PTFE fine powder under such a condition that the heat-treated molded article shows at least one endothermic peak which appears between an endothermic peak position of the fine powder and an endothermic peak position of a sintered product thereof on a differential scanning calorimeter chart and then is stretched along at least one direction.

Abstract: An apparatus for executing loop-back tests in a key service unit (50) of a key telephone system, including an ISDN interface unit (2) connected to an ISDN (30) is disclosed. When any one of speech channels of the ISDN (30) is not used, a predetermined test pattern data is transmitted through a time slot of the down-stream speech highway (3b) allocated to the unused speech channel to the ISDN interface unit (2). Then the test pattern data is returned back in the ISDN interface unit (2) and transmitted to a time slot of the up-stream speech highway (3a) allocated to the unused speech channel. The test pattern data transmitted to the up-stream speech highway is compared with the original test pattern data for executing the loop-back test.

Abstract: A recording apparatus includes an input circuit for inputting recording data, a process circuit for performing a recording operation on a photosensitive body on the basis of the recording data input from the input circuit, a designating circuit for designating a recording density, and a control circuit for controlling an operating condition of at least a high-voltage circuit on the basis of designation by the designating circuit. The process circuit includes the high-voltage circuit used for the recording operation.

Abstract: An image forming apparatus includes an area modulation means for forming a halftone image signal by area modulation according to input image data, and a recording unit for performing recording using a particle-type recording material according to the halftone image signal, wherein the length of a short side of a minimum modulation area of the area modulation means formed by the recording unit is set to 0.7-4 times an average particle size of the particle-type recording material.

Abstract: In a telephone system 1 connectable to both integrated service digital network (ISDN) lines 3a and 3b and a public subscriber telephone network (PSTN) line 7 and having a plurality of extension telephone sets 11a to 11d, the speech sound volume through the ISDN lines 3a and 3b is so adjusted as to become equal to that through the PSTN line 7, by changing the loss rate (i.e. gain) of digital pads 55 and 47 provided in ISDN interface units 5a and 5b. That is, a level confirmation tone is generated in the system 1; this tone is transmitted to a first extension telephone set 11a via only the ISDN on one hand and to a second extension telephone set 11b via both the ISDN and PSTN in series on the other hand; and the loss rate (i.e. gain) of the digital pads 55 and 47 are changed or adjusted so that the sound of the level confirmation tone can be heard at the same volume level by both the telephone sets 11a and 11b.

Abstract: A polytetrafluoroethylene porous material and a process for producing the same are disclosed, the material comprising a mixture of polytetrafluoroethylene having a number-average molecular weight of 2,000,000 or more and polytetrafluoroethylene having a number-average molecular weight of 1,000,000 or less, the material having been stretched at least uniaxially.

Abstract: A communication switching system is disclosed which includes a plurality of telephone sets and data terminals connected to an exchange. The data terminals have corresponding telephone sets. Other telephone sets operate independently. Information regarding the correspondence of the data terminals to the telephone sets is stored in the exchange. The telephone sets related to the data terminals initiate connection through the exchange of one data terminal to another data terminal. The telephone sets control the connection by the exchange using a two key sequence. The exchange controls the connection in accordance with data terminal/telephone set corresondence data stored in the exchange.

Abstract: A polytetrafluoroethylene porous material and a process for producing the same are disclosed, the material comprising a mixture of polytetrafluoroethylene having a number-average molecular weight of 2,000,000 or more and polytetrafluoroethylene having a number-average molecular weight of 1,000,000 or less, the material having been stretched at least uniaxially.

Abstract: In a key telephone system connectable to both ISDN and PSTN, for the purpose of compensation of a difference in speech signal level between ISDN and PSTN, digital pads are incorporated in an ISDN interface unit mounted on a key service unit of this system. In the digital pads, original PCM-code speech signals received/transmitted from/to the ISDN line are converted into PCM-code speech signal with a compensated speech signal level obtained by adding a selected gain to the original speech signal level. Since the difference in the speech signal level between ISDN and PSTN differs according to the conditions, an appropriate gain is selected from a plurality of previously prepared gains. That is, the relationship between telephone numbers and information signals indicative of the selected gain is registered in the key service unit.

Abstract: A digital communication apparatus in which time slots need not be switched, comprises a single channel highway in which a plurality of time slots are time-divisionally multiplexed, and first and second transmitting/receiving units connected to the highway. The first transmitting/receiving unit transmits a first signal supplied from a first terminal to the second transmitting/receiving unit through the highway using a first time slot designated from the plurality of time slots. The second transmitting/receiving unit outputs the first signal transmitted from the first transmitting/receiving unit through the highway using the designated first time slot to a second terminal. A second signal from the second terminal is transmitted to the first transmitting/receiving unit through the highway using a designated second time slot.

Abstract: In a digital key telephone system through which extension-to-extension calls can be made and incoming calls can be transferred between a master main installation and plural slave main installations, the master and slave main installations are interconnected through digital interface units provided for each installation in order to transmit and receive speech data and control data in digital code between the installations. The digital interface unit of the master main installation first designates an address of the slave main installation to which data are to be transmitted before data transmission, while the digital interface unit of the slave main installation receives data transmitted from the master main installation after address designation. Further, the addresses of the slave main installations can be designated together or separately.

Abstract: A telephone system which allows external releasing of a holding state set by a holding operation of a telephone set. A signal receiving circuit of the system receives a holding-state releasing signal such as a DTMF signal or the like sent from a central office line to release the hold state of the telephone set on the basis of an output of the circuit.