scholarly journals Influence of Cable Temperature Rise on PDC Method Test Results of Water Tree Aged Cables

2021 ◽  
Vol 261 ◽  
pp. 01025
Author(s):  
Jin Ming Guo ◽  
Fei Feng Wang
Keyword(s):  
Dielectric Loss ◽  
Temperature Rise ◽  
Low Frequency ◽  
Accelerated Aging ◽  
Test Results ◽  
Depolarization Current ◽  
Strong Polarization ◽  
Water Tree ◽  
Electrode Method ◽  
Test Result

There is a certain temperature rise in the field running cable because of the load bearing. To study the influence of cable temperature rise on the polarization and depolarization current (PDC) method, 10kV XLPE short cables were accelerated aging three months by water needle electrode method, and the PDC method was used to test the new and aged cables under constant humidity. The polarization and depolarization current of the cable samples was analyzed, and the conductivity and low frequency dielectric loss spectra were obtained and inspected. The results show that: in the experiment selected test temperature, the change laws of conductivity of the new and aged cables are the same, and the conductivity gradually rose after a slight drop in 40 °C; in the dielectric loss spectrum, the polarization of the new sample is low and the polarization loss changes little with temperature, and the dielectric loss is mainly affected by the conductivity, so the test result is clearly divided into two regions. And water tree aged samples have strong polarization and are obviously affected by temperature, so their low frequency dielectric loss showed the trend of first rising and then decreasing and the maximum appeared at 60 °C.

On Electric Field Distribution and Temperature Rise Effect of High Power VLF Antenna

2021 ◽  
Vol 36 (6) ◽  
pp. 684-696
Author(s):  
Xianqiang Li ◽  
Kedan Mao ◽  
Ao Wang ◽  
Ji Tian ◽  
Wenchuang Zhou
Keyword(s):  
Dielectric Loss ◽  
Electric Field ◽  
Field Distribution ◽  
High Power ◽  
Temperature Rise ◽  
Electric Field Distribution ◽  
Strong Electric Field ◽  
Low Frequency ◽  
Problem Analysis ◽  
Novel Approach

When a high-power very low frequency (VLF) communication system is in operation, the end of the antenna is in an alternating strong electric field environment. Due to dielectric loss, abnormal temperature rise may occur at the end of the antenna. To solve the problem, analysis on the electric field distribution and temperature rising effect at the end of the antenna is first carried out in this paper. The factors that affect the electric field distribution and temperature rising, including the amplitude and frequency of the excitation voltage, the diameter of the antenna conductor and the material properties of the outer sheath of the antenna, are studied in detail. A novel approach to improve the electric field distribution and to suppress temperature rising is proposed by designing a dielectric loss eliminator, and the effectiveness of the designed device is verified by simulation.

Correlation between AC breakdown strength and low frequency dielectric loss of water tree aged XLPE cables

1998 ◽  
Vol 13 (1) ◽  
pp. 40-45 ◽  
Author(s):  
S. Hvidsten ◽  
E. Ildstad ◽  
B. Holmgren ◽  
P. Werelius
Keyword(s):  
Dielectric Loss ◽  
Breakdown Strength ◽  
Low Frequency ◽  
Water Tree

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.

Reducing the low-frequency dielectric loss of CaCu3Ti4O12 ceramics by adding (In0.5Nb0.5)0.05Ti0.95O2

2021 ◽  
Vol 32 (7) ◽  
pp. 9324-9331
Author(s):  
Wentao Hao ◽  
Bo Yu ◽  
Panpan Xu ◽  
Li Sun ◽  
Ensi Cao ◽  
...  
Keyword(s):  
Dielectric Loss ◽  
Low Frequency

Fish Attraction with Pulsed Low-Frequency Sound

1968 ◽  
Vol 25 (7) ◽  
pp. 1441-1452 ◽  
Author(s):  
Joseph D. Richard
Keyword(s):  
Acoustic Stimulus ◽  
Low Frequency ◽  
Reef Fishes ◽  
Test Site ◽  
Acoustic Signals ◽  
Commercial Fisheries ◽  
Test Results ◽  
Potential Applications ◽  
Predatory Fishes ◽  
Underwater Television

A series of tests were conducted to determine the effectiveness of pulsed low-frequency acoustic signals for attracting fishes. The acoustic signals were contrived to simulate the hydrodynamically generated disturbances normally associated with active predation. Underwater television was used to observe fish arrivals during both control and test periods. Demersal predatory fishes were successfully attracted although they habituated rapidly to the acoustic stimulus. Members of the families Serranidae, Lutjanidae, and Pomadasyidae were particularly well represented among the fishes attracted. Sharks were also attracted in considerable numbers. Herbivorous reef fishes, although common around the test site, were not attracted. Possible relationships between the test results and the hearing capabilities of fishes are discussed. It is concluded that acoustic attraction techniques have potential applications in certain existing commercial fisheries.

Shock Test and Acceleration Analysis Methods of Marine Diesel Engines to Underwater Explosions

2013 ◽  
Vol 345 ◽  
pp. 64-67
Author(s):  
Jian Hua Zhao ◽  
Rui Bo Zhang ◽  
De Bin Zhu ◽  
Hong Bin Gao
Keyword(s):  
Diesel Engine ◽  
Low Frequency ◽  
Vibration Signal ◽  
Test Methods ◽  
Shock Acceleration ◽  
Test Results ◽  
Shock Test ◽  
Marine Diesel ◽  
Reduction Methods ◽  
Acceleration Analysis

Shock test of marine diesel engine is the important content for ship anti-shock research. Plentiful shock tests of equipments have been carried out abroad, but there is no detailed test methods of diesel engine. According to simulation results, 8-channel acceleration test points are determined. Because diesel engine is working, the measured shock acceleration is interfered by vibration signal. Orthogonal wavelet decomposition and wavelet noise reduction methods are used to separate shock component from test results. The seperated shock component consists of two parts. One is the low-frequency part caused by the shock from diesel foundation and then attenuation through the isolator, the other is the high-frequency part caused by the secondary shock of the retainer.

Influence of thermal treatments on the low frequency conductivity and microwave dielectric loss of CaTiO3 ceramics

2011 ◽  
Vol 176 (5) ◽  
pp. 401-405 ◽  
Author(s):  
Peng Hu ◽  
Huan Jiao ◽  
Chun-Hai Wang ◽  
Xiao-Ming Wang ◽  
Shi Ye ◽  
...  
Keyword(s):  
Dielectric Loss ◽  
Low Frequency ◽  
Thermal Treatments ◽  
Microwave Dielectric

scholarly journals Influenza colloidal gold method and blood routine tests combination for rapid diagnosis of influenza: a decision tree-based analysis

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Xiaoguang Li ◽  
Jing Chen ◽  
Fei Lin ◽  
Wei Wang ◽  
Jie Xu ◽  
...  
Keyword(s):  
Decision Tree ◽  
Predictive Value ◽  
Colloidal Gold ◽  
Influenza A ◽  
Clinical Manifestations ◽  
Rapid Test ◽  
Test Results ◽  
Tree Model ◽  
Routine Blood ◽  
Test Result

AbstractRapid influenza diagnosis can facilitate targeted treatment and reduce antibiotic misuse. However, diagnosis efficacy remains unclear. This study examined the efficacy of a colloidal gold rapid test for rapid influenza diagnosis. Clinical characteristics of 520 patients with influenza-like illness presenting at a fever outpatient clinic during two influenza seasons (2017–2018; 2018–2019) were evaluated. The clinical manifestations and results of routine blood, colloidal gold, and nucleic acid tests were used to construct a decision tree with three layers, nine nodes, and five terminal nodes. The combined positive predictive value of a positive colloidal gold test result and monocyte level within 10.95–12.55% was 88.2%. The combined negative predictive value of a negative colloidal gold test result and white blood cell count > 9.075 × 109/L was 84.9%. The decision-tree model showed the satisfactory accuracy of an early influenza diagnosis based on colloidal gold and routine blood test results.

Patient recommendations for content and design for electronic return of genetic test results: An interview study among patients who accessed their genetic test results online (Preprint)

2021 ◽  
Author(s):  
Diane M Korngiebel ◽  
Kathleen McGlone West
Keyword(s):  
Patient Preferences ◽  
Genetic Test ◽  
Smartphone Application ◽  
Patient Portal ◽  
Genetic Test Result ◽  
Test Results ◽  
User Centered Design ◽  
Detailed Report ◽  
Genetic Test Results ◽  
Test Result

BACKGROUND Genetic test results will be increasingly made available electronically as more patient-facing tools are developed; however, little research has been done that collects patient preferences for content and design before creating results templates. OBJECTIVE This study identifies patient preferences for electronic return of genetic test results, including what considerations should be prioritized for content and design. METHODS Following User-Centered Design methods, 59 interviews were conducted using semi-structured protocols. The interviews explored content and design issues for patient portal results return for patients who received electronic results for specific types of genetic tests (pharmacogenomic, hereditary blood disorders, and positive and negative risk results for heritable cancers) or who had electronically received any type of genetic test result as well as a non-genetic test result. RESULTS In general, a majority of participants felt that there always needed to be some clinician involvement in electronic results return and that electronic coversheets with simple summaries would be helpful for facilitating that. Coversheet summaries could accompany, but not replace, the more detailed report. Participants had specific suggestions for those results summaries, such as only reporting the information that was most important for patients to understand, including next steps, and to do so using clear language free of medical jargon. Electronic results return should also include explicit encouragement for patients to contact providers with questions. Finally, many participants preferred to manage their care using their smartphones, particularly in instances where they needed to access health information on the go. CONCLUSIONS Participants recommended that a patient-friendly front section accompany the more detailed report and made suggestions for organization, content, and wording. Many used their smartphones regularly to access test results, therefore, health systems and patient portal software vendors should accommodate smartphone application design and web portal design concomitantly when developing results return platforms. CLINICALTRIAL N/A

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