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Shue, Jack

Publications and source records attributed to Shue, Jack.

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Reversed Tantalum Capacitor Problem: A Failure to Fail, a Case Study

Reverse Ta capacitors are not expected to last for any length of time much less the over 74000 hours that they have been flying on Express (i.e. ExPRESS (Expedite the Processing of Experiments to the Space Station) Logistics Carrier (ELC) on the International Space Station. The report looks at the effects of moisture and temperature have on the capacitors. The removal of moisture has a far greater role in the survival of the capacitors than one would expect. Over 10000 hours of testing will be reviewed.

Shue, Jack↗
NASA NTRS2017

Ceramic Capacitor Delamination Problem

Update on ceramic capacitors issues since last years meeting. To including the story behind the issues behind the TIRS and SDO leaky capacitors.

Ceramic Capacitor↗
NASA NTRS2016

A Tale of Three Capacitor Problems

This talk will make a connection among several capacitor-related anomalies and failures that tie to some of the following conditions: reverse bias installation, cracked ceramic, and to minimal extent, elevated equivalent series resistance (ESR). In particular, we will briefly discuss anomalies we have experienced (1) in ground testing involving ceramic capacitors that had been hand soldered or had had touched-up solder joints, (2) in reverse-biased capacitors that have been operating for years on-orbit but that have experienced failures in ground operation and testing, and (3) in ceramic capacitors that exhibited an on-orbit latent defect resulting from cracks, and how these have come together. The talk will provide some lessons learned for recognizing and understanding anomalous behavior involving capacitors.

Anomalies↗
NASA NTRS2010

Power Electronics for the Next Generation

This slide presentation reviews some of the voltage requirements for future electronic devices. Particularly the allowed voltage variation on electronic logic types.

Shue, Jack↗
NASA NTRS2008

Guidelines for Reliable DC/DC Converters for Space Use

NESC saw the need to study the persistent failure of DC/DC Converters during ground testing and in flight, motivated investigation of causes and mitigation options. Research indicated misapplication and device quality to be root causes. The study took 20 months. Team included multiple NASA Centers : JPL, JSC, MSFC, GSFC Project Background

Plante, Jeannette↗
NASA NTRS2006

Thermal Imaging of Aerospace Battery Cells

Surface Thermal Profiles of Eagle Picher rabbit-ear 50Ah NiH2 and of Saft 40 Ah Li-ion cylindrical cells have been studied using ThermCAM S60 FLIR Systems. Popping Phenomenon in NiH2 cell is demonstrated Temperature gradient in NiH2 is slightly higher than normally considered, for example. Middle of stack to top or bottom is about 12.9 C compared to <7 C (may be due to passive cooling). Less than 1 C thermal gradient on the Li-Ion cell vessel surface. Significantly lower heat generation in Li-Ion cell compared to NiH2 cell. -May be due to a favorable charge method used for Li-Ion cell.

Shue, Jack↗
NASA NTRS2005

Advanced DC/DC Converters Towards Higher Volumetric Efficiencies For Space Applications

A new emphasis on planetary exploration by NASA drives the need for small, high power DC/DC converters which are functionally modular. NASA GSFC and other government space organizations are supporting technology development in the DC/DC converter area to both meet new needs and to promote more sources of supply. New technologies which enable miniaturization such as embedded passive technologies and thermal management using high thermal conductivity materials are features of the new designs. Construction of some simple DC/DC converter core circuits using embedded components was found to be successful for increasing volumetric efficiency to 37 W/inch. The embedded passives were also able to perform satisfactorily in this application in cryogenic temperatures.

Shaw, Harry↗
NASA NTRS2004

Marbles for the Imagination

The end-to-end test would verify the complex sequence of events from lander separation to landing. Due to the large distances involved and the significant delay time in sending a command and receiving verification, the lander needed to operate autonomously after it separated from the orbiter. It had to sense conditions, make decisions, and act accordingly. We were flying into a relatively unknown set of conditions-a Martian atmosphere of unknown pressure, density, and consistency to land on a surface of unknown altitude, and one which had an unknown bearing strength. In order to touch down safely on Mars the lander had to orient itself for descent and entry, modulate itself to maintain proper lift, pop a parachute, jettison its aeroshell, deploy landing legs and radar, ignite a terminal descent engine, and fly a given trajectory to the surface. Once on the surface, it would determine its orientation, raise the high-gain antenna, perform a sweep to locate Earth, and begin transmitting information. It was this complicated, autonomous sequence that the end-to-end test was to simulate.

Shue, Jack↗
NASA NTRS2004

Thermal Imaging of Aerospace Battery Cells

The objective of the research covered by this viewgraph presentation is to understand the thermal characteristics of a cylindrical aerospace battery cell by studying the surface thermal properties. The batteries tested include a nickel hydrogen cell (NiH2), and a lithium-ion cell (Li-ion).

Shue, Jack↗