Creating a Reliable Test Interface for a Unit Under Test

We present design concepts for calibrated hyperspectral image projectors (HIP) and related sources intended for system-level testing of instruments ranging from complex hyperspectral or multispectral imagers to simple filter radiometers. HIP, based on the same digital mirror arrays used in commercial digital light processing (DLP) displays, is capable of projecting any combination of many different arbitrarily programmable basis spectra into each pixel of the unit under test (UUT) at video frame rates. The resulting spectral and spatial content of the image entering the UUT can simulate, at typical video frame rates and integration times, realistic scenes to which the UUT will be exposed during use. Also, its spectral radiance can be measured with a calibrated spectroradiometer, such that the hyperspectral photon field entering the UUT is well known. Use of such generated scenes in a controlled laboratory setting would alleviate expensive field testing, allow better separation of environmental effects from instrument effects, and enable system-level performance testing and validation. Example potential applications include system-level testing of complex hyperspectral imaging instruments as implemented with data reduction algorithms when viewing realistic scenes, testing the performance of simple fighter-fighter infrared cameras under simulated adverse conditions, and hardware-in-the-loop testing of multispectral and hyperspectral systems.

Working Group on Blood Pressure Monitoring of the European Society of Hypertension International Protocol for validation of blood pressure measuring devices in adults Eoin O’Brien,Thomas Pickering, Roland Asmar, Martin Myers, Gianfranco Parati, Jan Staessen, Thomas Mengden, Yutaka Imai, Bernard Waeber and Paolo Palatini and with the statistical assistance of Neil Atkins and William Gerin, on behalf of the Working Group on Blood Pressure Monitoring of the European Society of Hypertension

As the complexity and functionality of electronic equipment increases over time, testing of modern day electronics has brought about the need for more complex stimulus and measurement capabilities. New methodologies such as Virtual and Synthetic Instrumentation have emerged to provide a more flexible ATE that can be re-configured to support a variety of technologies required by the modern day unit under test (UUT). Synthetic instruments can provide a solution to obsolescence in legacy ATEs and the flexibility required for commercial ATEs. A project was initiated to implement a prototype FPGA based reconfigurable Synthetic Instrument Core Framework that could directly interpret and use IEEE 1641 signals. IEEE Std 1641 provides for the accurate definition of stimulus and measurement signals, each of which are supported by a mathematical (functional) definition. During this project, both the software and hardware were developed for the core framework, which enabled the automatic generation and synthesis of synthetic instruments required to generate or measure a selection of IEEE 1641 signal models. The results obtained using the synthetic instruments could then be validated against simulations from EADS newWaveX™ signal development tool. This paper provides an overview of the project and the processes used to determine and implement an appropriate architecture for such a synthetic instrument system. It mainly focuses on the core of the system, i.e. the controller and codec subsystems. The paper concludes by discussing the suitability of an FPGA system for an IEEE 1641 compliant synthetic instrument system, comparing synthesized signals with simulated waveforms, and indicating suitable future enhancements to the system.

This research project aims to expand the capability of current US Navy Automated Test Equipment (ATE) family of testers known as the Consolidated Automated Support System (CASS). Industry research is now focused on breaking the historical construct of test equipment. Advances in the field of Synthetic Instruments have opened the door to test avionics in new ways. Every year new capabilities are developed using core hardware and increasingly capable software modules to create complex waveforms. This research creates a Digital Radio Frequency Memory (DRFM) Synthetic Instrument that can be programmed to perform a wide array of low latency Radio Frequency (RF) tests. Synthetic Instruments are defined as a concatenation of hardware and software modules used in combination to emulate a traditional piece of electronic instrumentation. This Synthetic Instrument couples high speed Analog-to-Digital Converters (ADC) to high speed Digital-to-Analog Converters (DAC) with Field Programmable Gate Arrays (FPGA) in between for digital signal processing. An RF front end is used to down convert the RF to baseband where it is sampled, modified, and up converted back to RF. The FPGA performs Digital Signal Processing (DSP) on the signal to achieve the desired output. Application of this DRFM in automated testing is demonstrated using a Reconfigurable Transportable Consolidated Automated Support System (RTCASS) tester at Naval Air Systems Command (NAVAIR) Jacksonville, FL. The Unit Under Test (UUT) is an ALQ-162 Defensive Electronic Countermeasures (DECM) receiver-transmitter. Ultra-low latency signals are generated to simulate enemy jamming stimulus. As the ALQ-162 detects and responds to the input, the DRFM switches to a new frequency. The time taken by the ALQ-162 to acquire, respond, and re-acquire is measured. This test confirms the internal Yttrium Iron Garnet (YIG) oscillator meets slew specifications. Currently Navy ATE can only test RF units using high latency steady state tests. This research project developed a supplemental unit that can be added to the VXI chassis in the CASS family of testers and conduct ultra-low latency active tests. The instrument acts as hardware-in-the-loop to perform real-time tests including a new capability to measure jamming response time from DECM avionics. Demonstrated performance capabilities include: latency <; 100 ns, output Spurious-Free Dynamic Range (SFDR) > 80 dBc, input SFDR > 60 dBc, frequency tuning resolution <; 2 Hz, and frequency settling time <; 0.5 ns. New RF capabilities developed by this effort parallel similar research ongoing for digital test instruments like the Teradyne High Speed Subsystem. Incorporating this Digital RF Memory synthetic instrument into current and future ATE will improve readiness and supportability of the fleet. Improvements demonstrated by this research project will expand the type and quantity of assets able to be tested by current and future ATE.

Simple harmonic waves and synthesized simple harmonic waves are widely used in the test of instruments. However, because of the errors caused by clearance of gear and time-delay error of FPGA, it is difficult to control servo electric cylinder in precise simple harmonic motion under high speed, high frequency and large load conditions. To solve the problem, a method of error compensation is proposed in this paper. In the method, a displacement sensor is fitted on the piston rod of the electric cylinder. By using the displacement sensor, the real-time displacement of the piston rod is obtained and fed back to the input of servo motor, then a closed loop control is realized. There is compensation of pulses in the next period of the synthetic waves. This paper uses FPGA as the processing core. The software mainly comprises a waveform generator, an Ethernet module, a memory module, a pulse generator, a pulse selector, a protection module, an error compensation module. A durability of shock absorbers is used as the testing platform. The durability mainly comprises a single electric cylinder, a servo motor for driving the electric cylinder, and the servo motor driver.

A tomographic technique for determination of the thermal power distribution in nuclear fuel assemblies is under development. The purpose is to provide an experimental validation tool for core simulation codes. Such codes are essential for the operation of nuclear power reactors, and validation is important in the process of improving and developing the codes as well as the fuel.The tomographic method is nonintrusive and offers large amounts of data within a normal revision shutdown. In earlier experimental investigations using a test platform, the method proved useful, demonstrating results of satisfying quality. However, the measuring setup also revealed nonfeasible properties related to transport, decontamination, and background radiation shielding.In this paper, the design of a new measuring device is presented. It is based on experiences from the test platform, but its size and weight make it advantageous regarding transports and decontamination. Moreover, the design inherently allows for more efficient background shielding.The latter has been investigated in a detailed study using the MCNP simulation code. The results confirm the high levels of background radiation observed in the test platform. It is also concluded that the shielding properties in the new design are sufficient.

Testing of an automotive fuel cell system

Objective To verify the accuracy of the results of special visual measurement instruments for heterphoric testing.Methods In this cross-sectional study,fifty healthy students served as subjects.The degree of heterphoria was measured by a special visual measurement instrument,the Maddox rod and a synoptophore.A one-way ANOVA and paired t test were used to calculate the data.Results ①The Maddox rod and synoptophore measured the highest amounts of esophoria,accounting for 38％ and 34％; hyperphoria was the least,accounting for 2％ and 4％.Measurements with the special visual measurement instrument found the highest amounts of esophoria plus hyperphoria,accounting for 36％; orthophoria was found the least,accounting for 4％.②Esophoria values measured in order from the most to the least were the Maddox rod,measurement instrument and synoptophore (F=3.18,P＜0.05).There was a significant difference between the Maddox rod and synoptophore (P＜0.05),but there were no significant differences between the Maddox rod and measurement instrument and the measurement instrument and the synoptophore (9＞0.05).Exophoria values measured from high to low were the Maddox,synoptophore and inspection instrument.There were no significant differences among the three methods (F=0.83,P＞0.05).Hyperphoria values measured from high to low were the measurement instrument,Maddox rod and synoptophore (F=6.34,P＜0.05).There were significant differences between the measurement instrument and synoptophore and the Maddox rod and synoptophore (P＜0.05),but there was no significant difference between the measurement instrument and Maddox rod (P＞0.05).③The dominant eye's value was higher than the nondominant eye's in esophoria,exophoria and hyperphoria,but only the Maddox rod measured a significant difference in esophoria (t=2.74,P＜0.01).Conclusion There were differences in the degree of heterphoria measured by the three instruments,but there was no significant difference between the measurement instrument and Maddox rod. Key words: Heterophoria; Visual function test; Com study

The development of a PC-based functional test platform that incorporates Statistical Process Control (SPC) and a failure analysis database is described. With Commercial Off-The-Shelf(COTS) tools available it is possible in a low volume high-mix environment to easily obtain basic statistical information on each test, develop an easily accessible database of information on failures, causes of failures and troubleshooting activities and increase test efficiency with minimal test development costs. A common test platform has been developed that can be configured to test a wide variety of sub-assemblies from digital controller cards to radio frequency (RF) modules. The platform consists of a PC with a multi-function data acquisition card and a General Purpose Interface Bus (GPIB) card for control of test instruments. Applications are linked with Dynamic Data Exchange (DDE) and the PCs are connected to the company's Local Area Network (LAN) so that test data can be accessed from throughout the plant. A key point is the implementation of SPC with this test platform. Statistics include process capability indices C/sub p/ and C/sub pk/ and failure rate. Test data is analyzed and used to make process improvements. Examples are presented. Since the entire system has been designed and built around established COTS software and hardware, additional capabilities can be easily added in the future. Some planned enhancements are described.

In this study, the effects of sitting position of the driver on the whiplash neck injury have been analyzed experimentally by using hybrid III series 50 percentile male crash test dummy. A testing platform consisting of vehicle ground, driver foot rest, driver seat and a 3-point seatbelt has been prepared. This testing platform and the instrumented crash test dummy are prepared for tests according to the Euro NCAP whiplash testing protocol. The prepared test set-up has been exposed to 3 different acceleration-time loading curves defined in the Euro NCAP whiplash testing protocol by performing sled tests. 9 different sled tests have been performed with the combinations of 3 different seating positions of the crash test dummy and 3 different acceleration-time loading curves. The sensor data obtained from the crash test dummy and high-speed videos taken are analyzed according to the injury assessments criteria defined in the Euro NCAP whiplash testing protocol and the criticality of the whiplash injury is defined. It is seen that the backset distance of the driver head with the headrest and the height difference of the top of the head of the driver with the headrest have a great importance on whiplash injuries.

The purpose of this study was to provide a critical review and comprehensive outline of published guidelines for the validation of monitors for indirect blood pressure (BP) measurement in light of recent research and practical clinical experience. Studies testing the reliability and validity of BP monitors and available guidelines for validation have been reviewed and compared. The validation studies of instruments for indirect BP measurement have used a wide variety of sample pools, BP ranges, protocols, reference instruments, and statistical procedures, thereby making it impossible to reach a consensus. Few existing recommendations for validation have been found to be incomplete with respect to BP in various physiological states, sequence of procedures, sample, and statistical analysis. A new sequence of procedures for validation, including assessment of instruments during exercise and in critical care, is introduced. Previously suggested sample sizes for study subjects, age, and BP groups, as well as margins of error, are statistically challenged. Insufficiency of linear relationship and aggregate agreement alone in determining the interchangeability between a reference and test instrument is demonstrated by quantification of agreement.

Background In clinical practice and in research, aphasia measurement instruments are used for many reasons: to screen and diagnose, to identify deficits and strengths, and to measure outcomes. A proliferation in available measurement instruments presents challenges to both the aphasia clinician and researcher and forms a barrier to optimal practice. There is a need for a comprehensive review of measurement instruments to identify the diversity of constructs measured by available tools and their cultural and linguistic applicability to the international aphasia community. Aims (1) To identify all available standardised measurement instruments which have been developed or tested with people with aphasia; and (2) To describe the construct/s measured, method of report, structure (components and scoring system), and availability of cultural/linguistic adaptations, of identified instruments. Methods and Procedures This scoping review is reported in alignment with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Studies were identified through searches of PUBMED, EMBASE, and CINAHL databases. Secondary searches of individual measurement instruments and hand searching were also undertaken. Two reviewers independently assessed titles, abstracts, and full-text articles. Inclusion criteria: studies reporting psychometric properties of measurement instruments, participants with aphasia (or their proxies), English language full-text journal articles. Data extracted: purpose, structure, and method of report of each instrument. The construct(s) reported to be measured by each instrument was classified according to the International Classification of Functioning, Disability and Health (ICF). Outcomes and Results A total of 3642 articles were identified through database searches. Following the removal of duplicates, 2879 articles were screened by title and abstract; with 334 articles undergoing full-text review. Secondary searches of individual measurement instruments and hand searching identified a further 99 publications. In total, 284 references for 143 measurement instruments were included in this review. Measurement instruments were classified by ICF component; the majority were reported to be measures of Body Functions (n = 94); followed by Activity/Participation (n = 23); Environmental Factors (n = 5); and quality of life/other constructs not within the ICF (n = 16). Five measured multiple ICF components. Conclusions and Implications This review identified 143 measurement instruments, developed or tested with people with aphasia. Classified according to the ICF, these instruments primarily measure Body Functions (n = 94). Some measurement instruments have undergone extensive cultural and linguistic translation/adaptation, however most have not. The resulting corpus of instruments provides a basis for the selection of measurement instruments in clinical and research settings.

The role of built in test (BIT) in electronic systems has grown in prominence with the advances in system complexity and concern over maintenance lifecycle costs of large systems. In an environment where standards drive system designs (and provide an avenue for focused advancement in technology), standards for BIT are very much in an evolutionary state. The reasons for advancing the effectiveness of BIT include reduced support overhead, greater, confidence in operation, and increased system availability. The cost of supporting military electronic systems (avionics, communications, and weapons systems) has driven much of the development in BIT technology. But what about the systems that support these end items that contain test and measurement instrumentation - such as automatic test equipment (ATE), simulators and avionics development suites? There has also been a beneficial effect on the maintenance and availability of these systems due to the infusion of BIT into their component assemblies. But the effect has been much more sporadic and fragmented. This paper looks at the state of BIT in test and measurement instruments, explain its affect on system readiness, and present ideas on how to improve BIT technologies and standards. This will not provide definitive answers to BIT development questions, since the factors that affect it are specific to the instrument itself. The topics covered in this paper are: definitions of built-in test, instrument BIT history, importance of BIT fault coverage and isolation in support systems, overview of BIT development process issues that limit the effectiveness of BIT Standards related to instrument BIT, making BIT more effective in support system maintenance and availability and conclusions.

&lt;p style="text-align:justify"&gt;The purposes of this research are (a) to make an instrument to measure the achievement of project-based digitalpreneurship learning in students; (b) to describe the quality of the project-based digitalpreneurship learning achievement assessment instrument for vocational high school students; (c) to measure the competence and skills. This study employed to research and development as its methodology, using a combination procedure between Oriondo and Antonio and, Mardapi. The development procedure includes three stages: instrument design, instrument testing, and measurement. A total of 795 students who participated in the study at 5 vocational high schools in Yogyakarta's special region served as responders. Data analysis in this development uses the content validity of the formula Aiken V Index, confirmatory factor analysis establishes the construct's validity, and construct reliability. Measurement instrument development. Research findings that (a) the instrument is ready to be used in the measurement; (b) the quality of the project-based digitalpreneruship learning achievement assessment instrument for vocational high school students is well tested. This is evidenced by the validity test which has a high score &gt;.8; The proof of construct validity in this study using CFA &gt; .5; GOF chi-square value with a critical value of df = 289, X2 = 323, p-value with a critical value of .079, RMSEA with a critical value of RMSEA .019 (≤ .08), SMRM with a critical value of SRMR 0.030 (≤ .05), CFI with a critical value of CFI .990 (&gt; .97), and an NFI with a critical value of NFI .989 ( &gt; .90); (c) the measurement results are identified in the process that needs to be improved again regarding the digitalpreneurship skills of vocational high school students.&lt;/p&gt;

The rapid evolution of advanced VLSI and VHSIC technologies, with advanced devices switching on time scales of less than 10psec creates new demands on high-speed diagnostic and testing instruments. The most important demands are the capability of contactless and noninvasive measurement of switching times and voltage states on internal nodes of VLSI ICs with a high time resolution (1–5 psec), a high voltage resolution (1–10 mV) in conjunction with a short measurement time, and a spatial resolution in the submicron range. It should be emphasized that these requirements have to be achieved simultaneously. In addition, it is desirable to have a diagnostic technique that is applicable to all semiconductor technologies rather than being limited to exclusively silicon- (Si) or gallium-arsenide- (GaAs) based circuitry.