Mehrzad Mahdavi

US Patent:

20080028453, Jan 31, 2008

Filed:

Mar 29, 2007

Appl. No.:

11/731011

Inventors:

Thinh Nguyen - Sugar Land TX, US
Shaun Cuttill - Katy TX, US
Timothy Nguyen - Houston TX, US
Mehrzad Mahdavi - Houston TX, US

International Classification:

H04L 9/32

US Classification:

726009000, 726010000, 726005000

Abstract:

A method for authenticating a user involves receiving a request from the user to access a resource, where the resource is associated with at least one authentication requirement, determining a trust level associated with access to the resource, obtaining user credentials based on the trust level associated with the resource, selecting an authentication method for authenticating the user based on the trust level associated with the resource, generating user authentication information based on the trust level associated with the resource and the user credentials obtained, where user authentication information relates to the user's environment while accessing the resource, sending the user authentication information to the resource, and granting access to the resource, if the user authentication information meets the at least one authentication requirement of the resource.

US Patent:

51285410, Jul 7, 1992

Filed:

Oct 5, 1987

Appl. No.:

7/104750

Inventors:

Mehrzad Mahdavi - Monmouth Junction NJ
Jean-Remy Olesen - Sugar Land TX
Donald K. Steinman - Missouri City TX
George C. Summerfield - Ann Arbor MI

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

G01V 510

US Classification:

250269

Abstract:

A borehole logging method for determining thermal neutron decay characteristics of a formation surrounding the borehole, comprises the following steps. The formation surrounding the borehole is irradiated from a location within the borehole with a burst of neutrons and indications of the concentration of the diffusing thermal neutrons are detected in at least three time gates following the burst of neutrons. Corresponding count rate signals in response to the detected neutrons are produced. Thereafter, the count rate signals are combined in a predetermined manner to separate a characteristic of the thermal neutron decay rate of the formation from associated neutron diffusion characteristics which are monotonically decreasing with time. The steps of irradiating, detecting and combining are then repeated at different depth locations within the borehole and a recording of the rate of decay of thermal neutrons as a function of borehole depth is produced.

US Patent:

55235565, Jun 4, 1996

Filed:

May 24, 1994

Appl. No.:

8/248811

Inventors:

Steve Meddaugh - Hamilton Square NJ
Mehrzad Mahdavi - North Brunswick NJ
Stefan Vajda - Belle Mead NJ

Assignee:

Schlumberger Technology Corporation - Ridgefield CT

International Classification:

H01J 4014

US Classification:

250214VT

Abstract:

A Cockcroft-Walton (CW) multiplying circuit is mounted to wrap around a cylindrical structure. A photomultiplier tube (PMT) has a photocathode which emits electrons and has dynodes connected to the CW multiplying circuit. The dynodes are biased to attract electrons from the photocathode. An electrical shield surrounds the PMT and the PMT nests within the shield. The cylindrical structure surrounds the shield and the shield nests within the cylindrical structure. The shield is a conductive material which electrically isolates the PMT from the CW multiplying circuit.

US Patent:

52351858, Aug 10, 1993

Filed:

Jan 9, 1992

Appl. No.:

7/819541

Inventors:

Paul Albats - Ridgefield CT
Russell C. Hertzog - Missouri City TX
Mehrzad Mahdavi - Monmouth Junction NJ

Assignee:

Schlumberger Technology Corporation - New York NY

International Classification:

G01V 510
G01V 514

US Classification:

250269

Abstract:

A tool which contains a pulsed accelerator neutron source and means for making timing measurements of the thermal neutron response in a localized portion of the environment immediately surrounding the borehole. Formation sigma is determined by parameterizing the detected thermal neutron decay curve, preferably with a diffusion model similar to that known in the art for determining formation sigma on the basis of gamma ray time distributions. In a more comprehensive embodiment of the present invention, which includes a gamma detector in the tool, formation sigma can be measured in parallel using both gamma ray and thermal neutron decay characteristics. Deviations between the neutron and gamma-based signals that occur as the tool traverses the borehole, provide useful indications of local effects immediately surrounding the borehole.

US Patent:

49470400, Aug 7, 1990

Filed:

Dec 20, 1989

Appl. No.:

7/455807

Inventors:

Mehrzad Mahdavi - Houston TX
Shivakumar Sitaraman - Houston TX

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

G01V 510

US Classification:

250266

Abstract:

A borehole logging method for determining the porosity of a formation surrounding the borehole, comprising the steps of: irradiating the formation surrounding the borehole from a location within the borehole with a burst of neutrons, detecting at a near detector indications of the concentration of thermal neutrons following the burst of neutrons and generating near count rate signals as a function of time in response thereto, detecting at a far detector indications of the concentration of thermal neutrons following the burst of neutrons and generating far count rate signals as a function of time in response thereto, fitting a count rate model to the near count rate signals to determine a near impulse formation count rate amplitude, fitting a count rate model to said far count rate signals to determine a far impulse formation count rate amplitude, determining the ratio of the near and far count rate signals as a characteristic proportional to the porosity of the formation.

US Patent:

20200157922, May 21, 2020

Filed:

Jan 23, 2020

Appl. No.:

16/750896

Inventors:

- Houston TX, US
Jason Scott PENNER - Pearland TX, US
Colin Albert TAIT - Tomball TX, US
Mehrzad MAHDAVI - Houston TX, US

International Classification:

E21B 41/00
E21B 47/00
E21B 43/12

Abstract:

The present disclosure describes implementation of wireless sensor packages to monitor various oilfield equipment health status, such as bearing wear and detect out-of-balance condition on reciprocating rod lifts (RRLs). Equipment health data can be collected, analyzed and stored by an IoT gateway, which is a small form-factor, ruggedized, low-power Intel processor computer running a novel message-oriented middleware software stack that leverages the MQTT protocol. Data may subsequently be transmitted to a cloud service via the internet via to a datacenter through SCADA, for analysis and action.