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Background Turning and repositioning devices (TRDs) help to reduce strain on caregivers, but clinicians question their effects on humidity and temperature (microclimate) at the skin surface that may increase risk of pressure ulcers. Objective To pilot the use of a standard test for support surfaces to compare microclimate at the skin surface in three scenarios: (1) on a low-air-loss (LAL) surface, (2) on a representative TRD with a basic underpad (TRDU) placed on a LAL surface, and (3) on a negative control with full occlusion. The results are designed to inform clinical decision-making in using a TRD on a LAL surface and the viability of using this test to study TRDs. Design Measuring humidity and temperature at the device-surface interface using a heated moisture-exuding bronze thermodynamic human model in a laboratory setting. Main outcome measure Humidity and temperature levels across 3 hours 15 minutes of continuous loading with a 45-second complete unloading to simulate a position change at 3 hours. Main results Relative humidity on the TRDU was below that on the LAL surface for the first 110 minutes and was markedly lower than the negative control for the remainder of humidity testing. Temperature on the TRDU was well below the negative control and negligibly higher than the surface alone throughout testing. The position change enhanced the effects of the TRDU. Conclusions The support surface standard test appears useful in evaluating TRDs. This TRD along with the basic underpad is more comparable to a LAL surface than to full occlusion in managing the microclimate of the skin and pressure ulcer risk.

During the last years applications for power modules with harsh environmental conditions have gained increasing importance. Static humidity tests with T = 85 °C and RH = 85% with high voltage have established as basic testing method for the humidity robustness of semiconductor power modules. The present work is showing the improvement of humidity robustness with respect to the established test methods. Electrical performance monitoring and analytic approaches to prove the results with respect to established work on the field of humidity testing.

Wirebond engineers and technicians primarily rely on three means by which to evaluate the integrity and reliability of a wirebond interconnect. Destruct/non-destruct pull test, ball shear, cross-sections, intermetallic coverage under the ball are tests used to evaluate the mechanical strength as part of process development and in line process controls. Reliability testing and evaluation involves these same tests after prolonged environmental exposure such as, temp cycling, burn-in, humidity testing etc. according to standards such as AEC-Q100. Much has been written about the above. A third and very important consideration in wirebonding is visual inspection of the deformed wire after wirebond formation. The amount of wire squash-out, placement of the bond on the pad relative to nearby circuitry, looping profiles and heel integrity are all very important aspects of wirebond interconnect inspection. Poor workmanship can lead to noncompliant bonds per visual inspection criteria and can directly impact the reliability of the finished product. Bond pad inspection prior to bonding is also a critical aspect that is often overlooked. Historically, MIL-STD-883 has served as a baseline set of visual specs related to wirebond, and package assembly in general. Many company quality documents reference MIL-STD-883 TM 2017 and TM 2010 and/or cut and paste the bond inspection criteria into internal documents. This paper critically reviews the wirebond visual inspection criteria contained in MIL-STD-883 relative to the requirements of a fully optimized modern day wirebond process.

Sensor components may markedly differ from typical silicon chips. Consequently, versatile attachment methods are required for their interconnections. Anisotropic conductive adhesives (ACA) are interesting materials for attachments of sensors due to their versatility. In this study reliability of ACA attached humidity sensors was studied in hygrothermal conditions. The reliability of the interconnections was found to be excellent even under prolonged exposure showing that high reliability can be achieved with ACA materials in sensor applications. publishedVersion

This paper proposes the appropriate waterproofing methods for underground structures after applying different types of waterproofing materials on the concrete test specimens and selecting the best results out of humidity testing in winter conditions. Results of the testing showed that the underground structures absolutely require relevant waterproofing application based on the environmental conditions; when applied with interior waterproofing, the results showed that the concrete maintained high level of humidity and reinforcing steel within the concrete layer corroded. However, when applied with exterior waterproofing, it was shown that the waterproofing layer prevent direct contact with water and concrete, thereby protecting the concrete structure and improving overall durability. It follows that during underground structure construction, exterior waterproofing methods are have shown by an effective method for improving the durability as well as providing a comfortable interior environment for users.

The effect of humidity on SiC Power MOSFET modules is investigated in an industrial application. Four modules are operated outdoor and four modules are operated indoor in identical setups, while their breakdown voltages are monitored regularly. The evolution of the leakage current, indicating humidity-induced degradation is observed.

Drying characteristics of Thomson seedless grape at different drying temperatures (45°C, 40 °C, 35 °C and 30 °C) were investigated in a Constant Temperature and Humidity Testing Machine. 8 different thin layer mathematical drying models are selected to fitting the date. The logarithmic drying model is satisfactorily to describe the drying process of grapes. In addition, this paper also calculated the moisture effective diffusivity (Deff) of Thompson seedless grape during drying process, and 45 °C has the maximum value 3.0702·10-11 m2/s. The energy of activation (Ea) is 59.03 kJ/mol. This means it will take 3279.44 kJ to remove 1kg water from the grape samples.

Traditionally, color trends are thought to cycle every 7 years. This is due, largely, to the extensive long-term exterior heat and humidity testing in Arizona and Florida for the automotive industry that requires several years to complete. Neutrals or classic colors such as blacks and whites tend endure over trend periods and are also statistically the best sellers in most industries. This is particularly true in more durable industries such as large appliances, exterior architecture and automotive. There is a certain value attached to each of these industries and the greater the resale opportunity, the more conservative or classic colors will dominate. Clearly, industries such as fashion or toys that are very immediate in their consumption and will have little opportunity for resale allow for color choices that can be more whimsical (fad-like) or reflective of current social and economic trends. Beauty products, including their packaging, tend to cycle more quickly with the fashion market so major colors change with the seasons or the annual fashion shows. This is also true, to a lesser extent to other types of personal care products and packaging. Female and children’s products cycle more frequently and men’s personal care tends to lag behind and has a much more limited color pallet that feels more automotive or sporty. That is not to say that these other industries do not pay attention to current social trends.

Thin silica coatings (15–60 nm) were deposited as barrier coatings on carbon steel by a flame assisted chemical vapor deposition (CVD) process. The silica-coated steel showed good corrosion properties in cyclic humidity testing (bare) and salt spray testing (painted). Electrochemical analysis was performed to investigate the corrosion mechanism. The study suggests that the corrosion starts at pin-holes and proceeds then further under galvanic coupling with the surrounding regions. We find that the corrosion rate is reduced by a factor 10 or more with respect to uncoated steel, depending on the testing conditions and type of silica coating.

A humidity sensor made of the natural polymer chitosan has been successfully fabricated in the film form by a solution casting method. Humidity testing was performed by placing a chitosan film sensor in a cooling machine room, model KT-2000 Ahu. The testing results showed that the output voltage values of chitosan film sensor increased with the increase in humidity percentage. For the increase in humidity percentage from 30 to 90% showed that the output voltage of chitosan film sensor increased from 32.19 to 138.75 mV. It was also found that the sensor evidenced good repeatability and stability during the testing. Therefore, chitosan has a great potential to be used as new sensing material for the humidity detection of which was cheaper and environmentally friendly.

In this work, the degradation of GaN-based packaged white light-emitting diodes (LEDs) caused by accelerated humidity testing will be investigated using non-destructive failure analysis tools, namely the mixed statistical distribution, spectrum analysis and parameters extraction. Physical failure analysis techniques are then used to verify and conclude the deduced failure mechanisms obtained by the non-destructive failure analysis tools.

This work investigates electrical pressure contacts based on a micro-spring with orders of magnitude smaller pitch and force than conventional pressure contacts. The springs are beams which curl out of the surface and can be used for wafer-scale testing and packaging. They are fabricated with standard wafer-scale thin film techniques and have been previously demonstrated on active silicon integrated circuits. Single springs and their electrical contacts are characterized with force versus compression and compression versus resistance measurements. Flip-chip packages with hundreds of micro-springs were assembled with 20-mum pad pitch and 40-mum spring pitch. Each spring operates with a force of approximately 0.01 g and contacts a gold pad. These packages are shown to have stable resistance values during both in-situ thermocycle (0degC to 125degC) and humidity testing (60degC at 95%RH). Spring electrical contacts inside the package are shown not to degrade during environmental testing through measurements of four-wire resistance and electrical isolation structures. High-speed glitch measurements are performed to confirm that the pressure contact does not have intermittent opens during thermocycling. These results suggest that a low-force solder-free pressure spring contact is a viable technology for next generation flip-chip packaging

Product reliability investigations typically include accelerated humidity testing. Originally, the “standard” test was a biased 85 °C/85% relative humidity (RH) lifetest for 1000 h. Recently, a substitute accelerated version of this test has been used. The accelerated version is called highly accelerated stress test (HAST). The HAST conditions are also biased, at 130 °C, 85%RH, and approximately 18 PSI overpressure. The duration of the HAST test is normally 96–100 h – to be equivalent to the 85/85 test. This study is intended to investigate thermal acceleration and show that equivalent HAST tests on compound semiconductors are more highly accelerated and could be conducted with much shorter durations.

Electrochromic (EC) glazings for architectural window systems must have desirable solar control properties, be designed for high-volume manufacture, and exhibit outstanding durability. This paper discusses performance and both real time and accelerated testing of prototype monolithic lithium-ion EC glazings in insulating glass units (IGUs). Outdoor exposure at New Jersey and Arizona (desert) test sites shows good switching performance under the different solar irradiance conditions. Accelerated test results include room temperature and elevated temperature electrochemical cycling, electrochemical cycling in combination with photo/thermal cycling, and temperature/humidity testing of IGUs.

The surface stability of NdBa 2 Cu 3 O 7− x thin film is utudied using the conditions referred to as standard accelerated humidity testing. NdBa 2 Cu 3 O 7− x thin film is compared with well studied YBa 2 Cu 3 O 7− x thin film by evaluating the surface resistance ( R s ) obtained from their film-based microstrip line resonators. The R s of the NdBa 2 Cu 3 O 7− x thin film indicates better stability than that of YBa 2 Cu 3 O 7− x in the low and relatively high microwave power range.

Submission of test components and representative MMICs to an extensive range of environmental and endurance tests has confirmed the suitability of polyimide as a dielectric layer for a high performance, reliable GaAs foundry process. In particular, the ability to withstand 1000 hours of 85 per cent RH, 85°C humidity testing has been demonstrated.

Humidity is one of the fundamental physical features of materials; the detection of water is one of the most frequently executed examinations. The following article presents problems connected with measurements of material humidity.

For calibration and intercomparison experiments, a thoron chamber with an inner volume of 300 l was designed based on a programmable constant temperature and humidity testing device in this work. The commercial lantern mantles enriched with (232)Th were used as the (220)Rn source and the mantles were set in 3×3×3 points of lattice style inside the chamber. Experimental studies showed that (220)Rn concentrations in the chamber could be easily controlled and adjusted from about 0.5 to 80 kBq m(-3) through manual settings of the relative humidity and temperature, and the spatial distribution of (220)Rn in the chamber was fairly homogeneous.

This paper focuses on the hardware and software design method of a new type of high efficient temperature and humidity testing cabinet. As the hardware core is based on the STC12C5616AD MCU, the entire hardware system is simpler and more reliable. By using sectional measurement of temperature and humidity, adopting expert PID control algorithm and using hardware and software compensation measures, the system dynamic and static quality and control precision is further improved. The system cabinet with a unique inner and outer double-loop structure improves the system efficiency and energy saving effect. Furthermore, the use of touch screen as input and output device, which is simpler to operate and more eye-catching, meets the different needs of consumers.

Reliability prediction models for microcircuits have been a function of steady-state temperature. Failure rates generated from accelerated temperature tests were extrapolated to predict system reliability at system use temperatures. This is now known to be completely inaccurate. Attempts are now being made to predict the reliability of plastic encapsulated microcircuits (PEMs) based on accelerated temperature/humidity testing. Failure rates generated due to corrosion failure mechanisms at these high stress levels are then extrapolated and used to predict system reliability at used temperature/humidity conditions. This paper discusses the fallacy of this approach. A new concept for the assurance of PEM corrosion resistance is proposed. It will be shown that today's best commercial practice suppliers have already addressed the design, materials, and processing issues of molded packaged microcircuits, and corrosion is no longer a mechanism of concern to the user.

INTRODUCTION Many pharmaceutical drug substances and drug products are photosensitive and will undergo photodegradation upon exposure to outdoor or indoor photon sources. The topic of photostability has been dealt with by the International Conference on Harmonization (ICH) as a special case of stability (ICH Topic Q1A), and guidelines for photostability testing are presented as an annex (ICH Topic Q1B) to the parent stability guideline. Photostability testing, however, presents many unique difficulties when compared with thermal and humidity testing outlined by ICH Q1A. Issues such as the choice of photon source, irradiation homogeneity, containers/sample holders, sample thickness, and orientation are just a few of the parameters that are critical to meaningful evaluation of the photostability of a drug substance or product. Furthermore, careful consideration should be given to the type of analytical testing performed as part of the control strategy for evaluation of photostability postexposure. Sample presentation, the manner in which the samples are prepared, packaged, and aligned relative to the photolysis source for photostability testing, can have a significant effect on the outcome of the photostability experiment. This chapter will provide some practical information about the critical parameters involved in photostability testing with respect to “presentation” of the sample to the photon source.

Extensive environmental testing is necessary to assess the ability of thin-film solar cells to survive launch and space operational conditions. Such testing is vital prior to the use of thin-film solar cells in space and the realization of their beneficial attributes. Included in these environmental analyses are the effects of humidity and thermal cycling. For humidity testing, this paper will present results from ground testing for environmental effects on amorphous-Si (a-Si) from one manufacturer, both bare and with coatings. For thermal cycling, the test cell will be bare. The test parameters and configurations will be tailored to support the upcoming AFRL Thin Film Solar Cell Experiment upon flight of the Deployable Structures Experiment (DSX).

This work investigates electrical pressure contacts based on a micro-spring with orders of magnitude smaller pitch and force than conventional pressure contacts. Flip-chip packages were assembled with hundreds of micro-springs at 20 mum pad-pitch, 40 mum spring-pitch, and an operating force of 0.01 gram on gold pads. These packages are shown to have stable resistance values during both in-situ thermocycle (0 degC to 125 degC) and humidity testing (60 degC at 95% RH). High-speed glitch measurements are performed to confirm the pressure contact does not have intermittent opens during thermocycling. These results suggest that a low-force solder-free pressure spring contact is a viable technology for next generation flip-chip packaging

In this work, the effect of temperature and moisture on joint resistance of Au bump and ACA is reported. A flip chip on glass (FCOG) test vehicle was used to study the joint resistance of Au bump and ACA after temperature cycling (-40/spl deg/C/125/spl deg/C), temperature humidity testing (85/spl deg/C/85%RH) and moisture preconditioning (MSL 1/3/5). In general, the results showed that Au bump and ACP has a better performance than Au bump and ACF during temperature cycling, temperature humidity testing and moisture preconditioning. The size of the Au bump and conductive fillers is found to an important factor in achieving a joint with low and stable resistance. For improved temperature and moisture performance, the use of a larger Au bump size with a larger conductive filler size is recommended for ACAs.

Corrosion protection behavior of SiNx coated silver-mirror investigated with electrochemical impedance spectroscopy and compared with results from humidity testing. A 3 A NiCrNx interlayer between SiNx and Ag afforded denser SiNx film and enhanced mirror-durability.

Temperature and humidity tests were performed on commercial grade fiber optic couplers, connectors, splices and optical,fiber. Both singlemode and multimode components were tested. Temperatures ranged from -54°C to +65°C or +85°C depending on the component application. In the humidity tests the relative humidity was maintained at greater than 95 percent above 20°C. Changes in optical transmittance of varying degrees and permanent damage were observed and recorded.

Accelerated corrosion tests were conducted by the Naval Surface Weapons Center on CAPTOR mine strongback bands. Strongback bands are part of the CAPTOR suspension system, which interfaces the mine to the delivery system of minelaying aircraft and surface ships. The laboratory tests were performed to recreate the stress corrosion cracking failures observed in CAPTOR stockpile storage. The tests were designed to produce the same failures during weeks of laboratory testing which occurred after several years of stockpile storage. This magnitude of accelerated testing required the use of aggressive corrosion test environments. Eight strongback bands, representing (known) problem bands (H925 heat treated 17-4PH stainless steel), the present-use bands (H1015 heat treated 17-4PH stainless steel), and the proposed replacement bands (Inconel 718), underwent side-by-side testing. Both (known) problem bands failed by stress corrosion cracking: the first during 28-day temperature and humidity testing, and the second during the subsequent 1000-hour salt spray test. None of the three present-use or three proposed replacement bands failed through the temperature and humidity test, salt spray test, and twelve months of outdoor exposure. These failures indicate that the test environments are sufficiently aggressive to recreate fleet-observed stress corrosion cracking failures, but in a much shorter time.

The precision wirebound resistor has undergone fairly extensive design changes within the last four or five years. The old "open bobbin" style resistor has been completely replaced by the molded thermosetting plastic enclosed resistor. The new design is capable of performing at extremely low and high temperatures, and will withstand rugged environmental testing, such as salt water immersion, humidity testing with polarizing voltage, and repeated temperature cycling. Improvements in design and in wire insulation have made it possible to operate these new units at higher internal temperatures, thus increasing their power handling capability. The protection afforded by the encapsulated housing makes the use of fine wire feasible in military resistors with consequent increase in maximum resistance value. This paper compares the old and new resistors, and discusses some of the factors which influenced the new precision resistor de- sign.

The physical adhesion between organic coating film and metallic surface can be enhanced by chemical interactions. This effect is achieved in this work by dibenzoylmethane which is added to an acrylic resin solution for the coating of carbon steel surface, as demonstrated by the formation of the iron complex on the metallic surface and the significant increase in corrosion resistance of the coating film in a condensing humidity test. Untersuchung von Acrylharz-Deckschichten mit Zusatz von Dibenzoylmethan zur Verbesserung des Korrosionsschutzes von C-haltigen Stahlen unter der Bedingung des Kondensation-Feuchtigkeit-Tests Die physikalische Bindung zwischen einer organischen Schutzschicht und einer metallischen Oberflache kann verstarkt werden, wenn chemische Wechselwirkungen auftreten. Dieser Effekt wird in dieser Arbeit durch Dibenzoylmethan erzielt, welches einer auf C-Stahl aufgetragenen Acryl-Harz-Schutzschicht zugesetzt wird. Die Wirkung beruht auf der Bildung eines Eisenkomplexes auf der Metalloberflache und last sich durch den eindeutigen Anstieg der Korrosionsschutzwirkung im Kondensations-Feuchtigkeit-Test zeigen.

The feasibility of implementing bias-humidity development testing to determine if field-like failure modes would result is demonstrated. Variables resulting in degradation were separated so causative variables could be identified. The studies were done on silicon solar cell modules from different manufacturers. Following each of the ten-day bias-humidity tests, the modules were examined, photographed, and tested. Limited bias-related changes were observed. (LEW)

This paper reviews all published life in humidity conditions vs life at 85C/85% RH for epoxy packages; 61 data points are used. An acceleration formula is described which provides direct extrapolation from test results in autoclave tests at up to at least 140C to low-humidity down to below 30XRH. This formula compares favorably with previously-published formulae. The possible effect of the Tg of the epoxy is recognized, and other high-temperature and low-humidity effects are disclosed. Recommendat ions are made for future tests, replacing 1000 hours at 85C/85%RH with a 20-hour test at 140C/100%RH, to reduce test time and increase test usefulness.