Anti-Islanding Test Results for Multiple PV Inverter Operations

2015 ◽  
pp. 147-151
Author(s):  
Byunggyu Yu ◽  
Youngseok Jung
Keyword(s):  
Test Results ◽  
Pv Inverter

scholarly journals Commercial PV Inverter IEEE 1547.1 Ride-Through Assessments Using an Automated PHIL Test Platform

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6936
Author(s):  
Nayeem Ninad ◽  
Estefan Apablaza-Arancibia ◽  
Michel Bui ◽  
Jay Johnson
Keyword(s):  
Test Procedure ◽  
Rate Of Change ◽  
Test Results ◽  
Distributed Energy ◽  
Pv Inverter ◽  
System Validation ◽  
Test Platform ◽  
Voltage Frequency ◽  
Grid Codes ◽  
First Time

As more countries seek solutions to their de-carbonization targets using renewable energy (RE) technologies, interconnection standards and national grid codes for distributed energy resources (DER) are being updated to support higher penetrations of RE and improve grid stability. Common grid-code revisions mandate DER devices, such as solar inverters and energy storage systems, ride-through (RT) voltage and frequency disturbances. This is necessary because as the percentage of generation from DER increases, there is a greater risk power system faults will cause many or all DER to trip, triggering a substantial load-generation imbalance and possible cascading blackout. This paper demonstrates for the first time a methodology to verify commercial DER devices are compliant to new voltage, frequency, and rate of change of frequency (ROCOF) RT requirements established in IEEE Std. 1547-2018. The methodology incorporates a software automation tool, called the SunSpec System Validation Platform (SVP), in combination with a hardware-in-the-loop (HIL) system to execute the IEEE Std. 1547.1-2020 RT test protocols. In this paper, the approach is validated with two commercial photovoltaic inverters, the test results are analyzed for compliance, and improvements to the test procedure are suggested.

Using Conventional Articulation Tests With Highly Unintelligible Children

1992 ◽  
Vol 23 (1) ◽  
pp. 52-60 ◽  
Author(s):  
Pamela G. Garn-Nunn ◽  
Vicki Martin
Keyword(s):  
Test Results ◽  
Phonological Processes ◽  
Rule Based ◽  
Severity Level ◽  
Error Sensitivity ◽  
Conventional Tests ◽  
Severity Levels ◽  
Conventional Test ◽  
Impaired Children

This study explored whether or not standard administration and scoring of conventional articulation tests accurately identified children as phonologically disordered and whether or not information from these tests established severity level and programming needs. Results of standard scoring procedures from the Assessment of Phonological Processes-Revised, the Goldman-Fristoe Test of Articulation, the Photo Articulation Test, and the Weiss Comprehensive Articulation Test were compared for 20 phonologically impaired children. All tests identified the children as phonologically delayed/disordered, but the conventional tests failed to clearly and consistently differentiate varying severity levels. Conventional test results also showed limitations in error sensitivity, ease of computation for scoring procedures, and implications for remediation programming. The use of some type of rule-based analysis for phonologically impaired children is highly recommended.

Vestibular Function and Motion Sickness Susceptibility: Videonystagmographic Evidence From Oculomotor and Caloric Tests

2020 ◽  
Vol 29 (2) ◽  
pp. 188-198
Author(s):  
Cynthia G. Fowler ◽  
Margaret Dallapiazza ◽  
Kathleen Talbot Hadsell
Keyword(s):  
Phase Velocity ◽  
Motion Sickness ◽  
Repeated Measures ◽  
Short Form ◽  
Vestibular Function ◽  
Slow Phase ◽  
Test Results ◽  
Normal Range ◽  
Slow Phase Velocity ◽  
Caloric Tests

Purpose Motion sickness (MS) is a common condition that affects millions of individuals. Although the condition is common and can be debilitating, little research has focused on the vestibular function associated with susceptibility to MS. One causal theory of MS is an asymmetry of vestibular function within or between ears. The purposes of this study, therefore, were (a) to determine if the vestibular system (oculomotor and caloric tests) in videonystagmography (VNG) is associated with susceptibility to MS and (b) to determine if these tests support the theory of an asymmetry between ears associated with MS susceptibility. Method VNG was used to measure oculomotor and caloric responses. Fifty young adults were recruited; 50 completed the oculomotor tests, and 31 completed the four caloric irrigations. MS susceptibility was evaluated with the Motion Sickness Susceptibility Questionnaire–Short Form; in this study, percent susceptibility ranged from 0% to 100% in the participants. Participants were divided into three susceptibility groups (Low, Mid, and High). Repeated-measures analyses of variance and pairwise comparisons determined significance among the groups on the VNG test results. Results Oculomotor test results revealed no significant differences among the MS susceptibility groups. Caloric stimuli elicited responses that were correlated positively with susceptibility to MS. Slow-phase velocity was slowest in the Low MS group compared to the Mid and High groups. There was no significant asymmetry between ears in any of the groups. Conclusions MS susceptibility was significantly and positively correlated with caloric slow-phase velocity. Although asymmetries between ears are purported to be associated with MS, asymmetries were not evident. Susceptibility to MS may contribute to interindividual variability of caloric responses within the normal range.

Item Context and /s/ Phone Articulation Test Results

1972 ◽  
Vol 15 (4) ◽  
pp. 852-860 ◽  
Author(s):  
Zoe Zehel ◽  
Ralph L. Shelton ◽  
William B. Arndt ◽  
Virginia Wright ◽  
Mary Elbert
Keyword(s):  
Test Score ◽  
Sound Production ◽  
Broad Context ◽  
Test Results ◽  
Production Task ◽  
Test Result

Fourteen children who misarticulated some phones of the /s/ phoneme were tape recorded articulating several lists of items involving /s/. The lists included the Mc-Donald Deep Test for /s/, three lists similar to McDonald’s but altered in broad context, and an /s/ sound production task. Scores from lists were correlated, compared for differences in means, or both. Item sets determined by immediate context were also compared for differences between means. All lists were found to be significantly correlated. The comparison of means indicated that both broad and immediate context were related to test result. The estimated “omega square” statistic was used to evaluate the percentage of test score variance attributable to context.

The Labeling Problem in Aphasia

1986 ◽  
Vol 51 (2) ◽  
pp. 176-180 ◽  
Author(s):  
Audrey L. Holland ◽  
Davida Fromm ◽  
Carol S. Swindell
Keyword(s):  
Speech Disorders ◽  
Case Description ◽  
Test Results ◽  
Apraxia Of Speech ◽  
Poor Agreement ◽  
Motor Speech ◽  
Motor Speech Disorders ◽  
Communication Difficulties ◽  
Token Test ◽  
Primary Problem

Twenty-five "experts" on neurogenic motor speech disorders participated in a tutorial exercise. Each was given information on M, a patient who had communication difficulties as the result of stroke, and asked to complete a questionnaire about his problem. The information included a detailed case description, an audiotape of M's speech obtained at 4, 9, 13, and 17 days post-stroke, and test results from the Western Aphasia Battery, the Token Test, and a battery for apraxia of speech. The experts were in excellent agreement on M's primary problem, although it was called by seven different names. The experts were in poor agreement on his secondary problem(s), e.g., the presence and type of aphasia and dysarthria. The results suggest that labeling is difficult, even for "experts." Furthermore, the practicing clinician needs to be sensitive to the likelihood of more than one coexisting problem.

Modified Earpieces and CROS for High Frequency Hearing Losses

1968 ◽  
Vol 11 (1) ◽  
pp. 204-218 ◽  
Author(s):  
Elizabeth Dodds ◽  
Earl Harford
Keyword(s):  
Hearing Loss ◽  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Sound Field ◽  
Intensity Level ◽  
Test Results ◽  
High Frequency Hearing Loss ◽  
Increased Sensitivity ◽  
Difficult Cases

Persons with a high frequency hearing loss are difficult cases for whom to find suitable amplification. We have experienced some success with this problem in our Hearing Clinics using a specially designed earmold with a hearing aid. Thirty-five cases with high frequency hearing losses were selected from our clinical files for analysis of test results using standard, vented, and open earpieces. A statistical analysis of test results revealed that PB scores in sound field, using an average conversational intensity level (70 dB SPL), were enhanced when utilizing any one of the three earmolds. This result was due undoubtedly to increased sensitivity provided by the hearing aid. Only the open earmold used with a CROS hearing aid resulted in a significant improvement in discrimination when compared with the group’s unaided PB score under earphones or when comparing inter-earmold scores. These findings suggest that the inclusion of the open earmold with a CROS aid in the audiologist’s armamentarium should increase his flexibility in selecting hearing aids for persons with a high frequency hearing loss.

Entrapment Neuropathies: Electrodiagnostic Criteria

2019 ◽  
Vol 24 (6) ◽  
pp. 12-15
Author(s):  
Jay Blaisdell ◽  
James B. Talmage
Keyword(s):  
Nerve Conduction ◽  
Task Force ◽  
Conduction Block ◽  
Cubital Tunnel Syndrome ◽  
Conduction Delay ◽  
Test Results ◽  
Sixth Edition ◽  
Entrapment Neuropathies ◽  
Axon Loss ◽  
Tunnel Syndrome

Abstract Like the diagnosis-based impairment (DBI) method and the range-of-motion (ROM) method for rating permanent impairment, the approach for rating compression or entrapment neuropathy in the upper extremity (eg, carpal tunnel syndrome [CTS]) is a separate and distinct methodology in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition. Rating entrapment neuropathies is similar to the DBI method because the evaluator uses three grade modifiers (ie, test findings, functional history, and physical evaluation findings), but the way these modifiers are applied is different from that in the DBI method. Notably, the evaluator must have valid nerve conduction test results and cannot diagnose or rate nerve entrapment or compression without them; postoperative nerve conduction studies are not necessary for impairment rating purposes. The AMA Guides, Sixth Edition, uses criteria that match those established by the Normative Data Task Force and endorsed by the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM); evaluators should be aware of updated definitions of normal from AANEM. It is possible that some patients may be diagnosed with carpal or cubital tunnel syndrome for treatment but will not qualify for that diagnosis for impairment rating; evaluating physicians must be familiar with electrodiagnostic test results to interpret them and determine if they confirm to the criteria for conduction delay, conduction block, or axon loss; if this is not the case, the evaluator may use the DBI method with the diagnosis of nonspecific pain.

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