Chao J Liu, 661571 67Th St APT 3D, Brooklyn, NY 11219

4128891, Dec 5, 1978

Dec 30, 1976

5/755892

Yeong S. Lin - Mt. Kisco NY
Chao N. Liu - Yorktown Heights NY
Donald T. Tang - Mt. Kisco NY

International Business Machines Corporation - Armonk NY

G06F 700
G06F 1300
G11C 1114
G11C 1908

364900

A relational data base system utilizing magnetic bubble domain storage. The bubble domain storage is located on a magnetic chip and includes storage circuitry for storing bubble domains in columns and rows. The bubble domains are coded to represent data, and the rows and columns of bubbles correspond to tables of data which are determined by various relations. Current activated transfer gates located on the magnetic chip are used to select a particular row or a particular column of bubble domains for accessing. The magnetic chip also includes a write circuit for writing bubble domains into storage and a read circuit for reading bubble domains removed from storage. Located off the magnetic chip are column addressing circuits, row addressing circuits, interface circuitry, and a computer central processing unit. The interface circuitry is located between the central processing unit and the bubble domain storage chip, while the column and row addressing circuits provide inputs to a transfer control circuit that is used to activate selected current carrying lines when it is determined to access a particular row or column of bubbles in storage. New information can be entered into any of the stored tables of bubble domains, and information can be removed from any of the stored tables.

4190747, Feb 26, 1980

Apr 5, 1978

5/893795

Alexander Feiner - Rumson NJ
Chao Kai Liu - Matawan NJ
Sigurd G. Waaben - Princeton NJ

Bell Telephone Laboratories, Incorporated - Murray Hill NJ

H04B 158
H04B 900

179170NC

A remote gain controlled optocoupled device is disclosed utilizing a DC reference voltage in the output section to compensate for variations in the optocoupling characteristics of the circuit. The DC voltage level output of the photodetector, which is a function of the light transfer characteristics of the circuit, is compared to a remotely controlled reference DC level. The output AC signal level, which substantially tracks the DC voltage output, is gain adjusted under control of the compared DC voltage levels.

4132870, Jan 2, 1979

Nov 3, 1977

5/848208

Chao Kai Liu - Matawan NJ

Bell Telephone Laboratories, Incorporated - Murray Hill NJ

H04M 100

179 81R

There is disclosed a protective coupler circuit of the circuit breaker type having a relay contact inserted in the communication line between the key telephone station and the central office in order to protect the central office line from hazardous voltages. A longitudinal unbalance detector is coupled with a metallic high voltage detector to control the relay operation. Circuitry is provided to operate in conjunction with the ring detection circuitry of the key telephone unit to insure proper circuit operation when ringing potential is present on the communication line even though that potential is over the threshold level of the hazardous voltage protector.

3991280, Nov 9, 1976

May 23, 1975

5/580293

Dennis Bryan James - Rumson NJ
Chao Kai Liu - Matawan NJ
Robert McKee Smith - Holmdel NJ

Bell Telephone Laboratories, Incorporated - Murray Hill NJ

H04M 356

179 18BC

In order to reduce the signal loss in a telephone line switching and conferencing system there is interposed between each line and the switching matrix a monobus port circuit arranged to convert a transmitted telephone signal into an equivalent current source. The currents from several monobus circuits are added in a bus resistor before distribution back to the individual monobus circuit where the original signal is subtracted from the bus signal. The resultant signal is transmitted to the telephone receiver. When the switching matrix crosspoint resistance is negligible, the component of the bus voltage measured at the current source output which results from current generated from each line is equal and opposite in magnitude to the voltage generated in the line. In any given line these voltages cancel each other, thereby eliminating the feedback signal. In situations where it is desired to use crosspoints having an unknown resistance, the voltage returned from the monobus does not exactly match the locally generated voltage because of the voltage drop across the crosspoint and thus a feedback signal of unknown magnitude is applied to the telephone line.

4004103, Jan 18, 1977

Oct 15, 1975

5/622516

Chao Kai Liu - Matawan NJ
Douglas Charles Smith - Locust NJ

Bell Telephone Laboratories, Incorporated - Murray Hill NJ

H04Q 342
H04Q 356

179 18EA

A plurality of idle paths through a multistage switching network which are capable of establishing a connection between a particular line and a particular trunk are identified. Repeated selection of paths identified as idle, but actually out-of-service, is avoided by selecting successively different ones of the identified idle paths in a pseudorandom manner to complete the connection between the line and the trunk. The pseudorandom path selection is accomplished in response to predetermined portions of a pseudorandom pattern of binary bits.

3990060, Nov 2, 1976

Mar 27, 1974

5/455425

Yeong S. Lin - Mount Kisco NY
Chao N. Liu - Yorktown Heights NY
Donald T. Tang - Yorktown Heights NY

International Business Machines Corporation - Armonk NY

G11C 1114
G11C 1908

340174TF

The data stored in a coincident block access bubble domain memory with bit-organized chips is encrypted by skewing or permuting selected word bits by predetermined amounts. This is implemented by providing an additional current loop on some or all of the chips which overlies the major loop pattern and has nodes at the similar vector poles of the major loop. The proper energization of selected ones of these additional current loops, under the control of a security key, inhibits or suppresses the advance of the bubble domains in the corresponding major loops for a predetermined number of cycles of the in-plane propagating field, thus skewing the word bits in these chips with respect to the remaining word bits in the unsuppressed chips. Decryption is accomplished by further inhibiting the same major loops for the necessary number of cycles to restore word bit synchronization throughout the memory.

4128829, Dec 5, 1978

Dec 30, 1977

5/866190

Noel M. Herbst - Mount Kisco NY
Chao N. Liu - Yorktown Heights NY

International Business Machines Corporation - Armonk NY

G06K 910

3401463SY

Method and apparatus are disclosed for verifying a sample signature based on comparison of the dynamics of a reference and a sample signature. More particularly, second derivative values of pen displacements (i. e. acceleration) and continuous pressure pattern signals are periodically sampled for both a reference and sample signature and a comparison of these second derivative values and pressure patterns is made. To effect the comparisons the two groups (reference and sample) of both second derivative and pressure pattern signals are segmented and corresponding segments are individually correlated. Successive comparisons of the same segment pairs are performed utilizing successive shifting of the phases between the two segments being correlated to find regions of highest possible correlation. A running account of the maximum cross correlation values for all of the segment pairs of the two signatures are kept. Finally, these maximum values obtained for each segment pair comparison are combined and this resultant correlation value is utilized as a verification indicator.

4142175, Feb 27, 1979

Jun 12, 1978

5/914651

Noel M. Herbst - Mount Kisco NY
Chao N. Liu - Yorktown Heights NY
Hugo A. Panissidi - Peekskill NY

International Business Machines Corporation - Armonk NY

G01L 516

3401463SY

A pressure sensing device having applicability as a simple pressure sensor and which is particularly adapted for use as a pen in a Signature Verification System, said device including a unique mounting structure for the pressure sensing stylus by flexible support means mounted on a substantially rigid base. The support means has a pressure sensing element mounted thereon. The flexible support means comprises two spaced members so disposed that their deflections and the output of the pressure sensing element are substantially independent of the angle of pressure on the stylus. In the special purpose embodiment useful for Signature Verification the stylus comprises a pen and the device further includes two orthogonally disposed accelerometers for sensing accelerations of said pen during the writing of a signature.