scholarly journals Changes of Insulation Properties of Photovoltaic Cables Caused by Ageing Treatment

2020 ◽  
Vol 6 (1) ◽  
pp. 6-9 ◽  
Author(s):  
Juraj Packa ◽  
Vladimir Kujan ◽  
Daniel Štrkula ◽  
Vladimír Šály ◽  
Milan Perný
Keyword(s):  
Power Plants ◽  
Real Life ◽  
Life Time ◽  
Operating Conditions ◽  
Solar Panels ◽  
Font Size ◽  
Long Term Stability ◽  
Cable Systems

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">An important part of the photovoltaic power plants are cable systems. The dielectric properties of cables, reliability and durability depend on quality of production processes, operating conditions and degradation factors, as well. Expected lifetime of cable systems is more than 20-30 years in general. Their failure free operation and long-term stability of properties has a direct impact on the economic return of the investments. According to our experiences the tests in compliance with valid standards are not adequate to verify real life time during operation. Photovoltaic cables intended for use in outdoor applications for the connection between the solar panels and possible connection between panels and inverter were chosen for our experiments. <span style="-ms-layout-grid-mode: line;">The changes </span>of insulation resistance and breakdown voltage caused by some degradation factors, mainly water, are presented. This research was inspired by real failure in operation.</span>

Long-Term Effectiveness of Fingolimod for Multiple Sclerosis in a Real-World Clinical Setting

2021 ◽  
pp. 1-6
Author(s):  
Cihat Uzunköprü ◽  
Yesim Beckmann ◽  
Sabiha Türe
Keyword(s):  
Quality Of Life ◽  
Multiple Sclerosis ◽  
Real Life ◽  
Life Assessment ◽  
Health Related Quality ◽  
Serious Adverse Events ◽  
Related Quality ◽  
Health Related

<b><i>Introduction:</i></b> The primary aim of the present study was to evaluate the long-term efficacy of fingolimod in patients with multiple sclerosis (MS); secondary aims were to describe the safety of fingolimod with the evaluation of treatment satisfaction and impact on the quality of life in real life. <b><i>Methods:</i></b> We collected clinical, demographical, neuroradiological, and treatment data, including pre- and posttreatment status health-related quality of life from 286 MS patients consecutively treated with fingolimod. Clinical assessment was based on the Expanded Disability Status Scale (EDSS), and quality of life assessment was performed with MS-related quality of life inventory (MSQOLI). The data were recorded at baseline and every 6 months for 2 years. <b><i>Results:</i></b> One hundred and fourteen males and 172 females were enrolled. The annualized relapse rate and EDSS showed a statistically significant reduction during the observation period (<i>p</i> &#x3c; 0.001). The patients also demonstrated substantial improvements in magnetic resonance imaging (MRI) outcomes (<i>p</i> &#x3c; 0.001). Health-related quality of life scores improved significantly between baseline and 24-month visit (<i>p</i> &#x3c; 0.001). No serious adverse events occurred. <b><i>Conclusion:</i></b> In our cohort, fingolimod treatment was associated with reduced relapse, MRI activity, and improved EDSS and MSQOLI scores. Additionally, fingolimod has been able to maintain its effectiveness over a considerable long period of treatment.

Ni-based bimetallic nano-catalysts anchored on BaZr0.4Ce0.4Y0.1Yb0.1O3−δ for internal steam reforming of methane in a low-temperature proton-conducting ceramic fuel cell

2021 ◽  
Author(s):  
Kyungpyo Hong ◽  
Stephanie Nadya Sutanto ◽  
Jeong A. Lee ◽  
Jongsup Hong
Keyword(s):  
Steam Reforming ◽  
Low Temperatures ◽  
Operating Conditions ◽  
Hydrogen Yield ◽  
Carbon Formation ◽  
Long Term Stability ◽  
Ceramic Fuel Cell ◽  
Ceramic Fuel ◽  
Nano Catalysts

Ni–Rh and Ni–Co nano-scale alloys exhibit high methane conversion, hydrogen yield, resistance to carbon formation, and long-term stability at low temperatures, allowing them to cope with the various operating conditions of direct methane-fueled PCFCs.

Determination of Long-Term Stability and Quality of HT-PEM MEAs

2018 ◽  
Vol 86 (13) ◽  
pp. 301-314
Author(s):  
Maren Rastedt ◽  
Julian Büsselmann ◽  
Tomas Klicpera ◽  
Karsten Reinwald ◽  
Nadine Pilinski ◽  
...  
Keyword(s):  
Term Stability ◽  
Long Term Stability

Long Term Performance of PE4710 Materials in Disinfectant Treated Nuclear Raw Water Systems

2013 ◽  
Author(s):  
Alexander M. Summe ◽  
Douglas P. Munson ◽  
Kenneth Oliphant ◽  
Sarah Chung
Keyword(s):  
Power Plants ◽  
Slow Crack Growth ◽  
Life Time ◽  
Water Systems ◽  
Superior Performance ◽  
Mechanical Degradation ◽  
Service Water ◽  
Long Term Performance ◽  
Term Performance

Degradation of service water systems is a major issue facing nuclear power plants and many plants will require repair or replacement of existing carbon steel piping components. High-density polyethylene (HDPE) has been used in non-safety service water systems for over ten years and has demonstrated superior performance. However, there still exist knowledge gaps around material properties, inspectability, and long-term performance. Specifically, there is a lack of insight on the aging of HDPE piping in disinfectant treated service water systems. This paper summarizes the methodology and results of predicting the expected life time of HDPE piping exposed to oxidizing biocides in numerous end-use scenarios. The aging mechanism of concern is Stage III Chemical-Mechanical degradation, where the polymer is oxidized by biocides and then experiences slow crack growth (SCG). An Aging Model is used to provide general predictions of pipe service life. The results were analyzed for trends and limiting or sensitive operating parameters were identified. For most applications, the specific resin used in the model demonstrated good performance for lifetimes of well over 40 years.

scholarly journals Validation of the IASI FORLI/Eumetsat ozone products using satellite (GOME-2), ground-based (Brewer-Dobson, SAOZ) and ozonesonde measurements

2018 ◽  
Author(s):  
Anne Boynard ◽  
Daniel Hurtmans ◽  
Katerina Garane ◽  
Florence Goutail ◽  
Juliette Hadji-Lazaro ◽  
...  
Keyword(s):  
A Priori ◽  
Long Term Stability ◽  
Comparison Results ◽  
Independent Observations ◽  
Mean Differences ◽  
A Priori Uncertainty ◽  
The Tropics ◽  
Global Mean

Abstract. This paper assesses the quality of IASI/Metop-A (IASI-A) and IASI/Metop-B (IASI-B) ozone (O3) products (total and partial O3 columns) retrieved with the Fast Optimal Retrievals on Layers for IASI Ozone (FORLI-O3) v20151001 software for nine years (2008–2017) through an extensive inter-comparison and validation exercise using independent observations (satellite, ground-based and ozonesonde). IASI-A and IASI-B Total O3 Columns (TOCs) are generally consistent, with a global mean difference less than 0.3 % for both day- and nighttime measurements, IASI-A being slightly higher than IASI-B. A global difference less than 2.4 % is found for the tropospheric (TROPO) O3 column product (IASI-A being lower than IASI-B), which is partly due to a temporary issue related to IASI-A viewing angle in 2015. Our validation shows that IASI-A and IASI-B TOCs are consistent with GOME-2, Dobson, Brewer and SAOZ retrieved ones, with global mean differences in the range 0.1–2 % depending on the instruments. The IASI-A and ground-based TOC comparison for the period 2008–July 2017 shows good long-term stability (negative trends within 3 % decade−1). The comparison results between IASI-A and IASI-B against smoothed ozonesonde partial O3 columns vary in altitude and latitude, with maximum standard deviation for the 300–150 hPa column (20–40 %) due to strong ozone variability and a priori uncertainty. The worst agreement with the ozonesondes and with UV-vis retrieved TOC [satellite and ground] is found at the southern high latitudes. Compared to ozonesonde data, IASI-A and IASI-B O3 products overestimate the O3 abundance in the stratosphere (up to 20 % for the 150–25 hPa column) and underestimates the O3 abundance in the troposphere (within 10 % for the mid-latitudes and ~ 18 % for the tropics). Based on the period 2011–2016, non-significant drift is found for the northern hemispheric tropospheric columns while a small drift prevails for the period before 2011.

scholarly journals Exposure of Ceramics and Ceramic Matrix Composites in Simulated and Actual Combustor Environments

2000 ◽  
Vol 122 (2) ◽  
pp. 212-218 ◽  
Author(s):  
Karren L. More ◽  
Peter F. Tortorelli ◽  
Mattison K. Ferber ◽  
Larry R. Walker ◽  
James R. Keiser ◽  
...  
Keyword(s):  
Ceramic Matrix Composite ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Surface Damage ◽  
Operating Conditions ◽  
Matrix Composites ◽  
Long Term Stability ◽  
Recession Rates ◽  
Combustor Liner

A high-temperature, high-pressure, tube furnace has been used to evaluate the long term stability of different monolithic ceramic and ceramic matrix composite materials in a simulated combustor environment. All of the tests have been run at 150 psia, 1204°C, and 15 percent steam in incremental 500 h runs. The major advantage of this system is the high sample throughput; >20 samples can be exposed in each tube at the same time under similar exposure conditions. Microstructural evaluations of the samples were conducted after each 500 h exposure to characterize the extent of surface damage, to calculate surface recession rates, and to determine degradation mechanisms for the different materials. The validity of this exposure rig for simulating real combustor environments was established by comparing materials exposed in the test rig and combustor liner materials exposed for similar times in an actual gas turbine combustor under commercial operating conditions. [S0742-4795(00)02402-9]

scholarly journals Long-Term Stability of Ferroelectret Energy Harvesters

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 42 ◽  
Author(s):  
Muhammed Kayaharman ◽  
Taylan Das ◽  
Gregory Seviora ◽  
Resul Saritas ◽  
Eihab Abdel-Rahman ◽  
...  
Keyword(s):  
Output Power ◽  
Operating Conditions ◽  
Constant Stress ◽  
Center Frequency ◽  
Term Stability ◽  
Energy Harvesters ◽  
Long Term Stability ◽  
Stress Cycling ◽  
Piezoelectric Charge

Cellular polypropylene (PP) has been recently used in energy harvesting applications. In this work, we investigate its viability and long-term stability under various operating conditions. Specifically, the effect of constant stress and stress cycling on output power and long-term stability of ferroelectret energy harvesters is analyzed. Our findings show that after 112 days constant stress significantly increases the piezoelectric charge constant d 33 and output power from 0.51 μW for a stress-free harvester to 2.71 μW. It also increases the harvester center frequency from 450 to 700 Hz and decreases its optimal resistance from 7 to 5.5 M Ω .

Turbo Gas Power Plants Performance Evaluation for Putting Into Commercial Operation

2009 ◽  
Author(s):  
Erik Rosado Tamariz ◽  
Norberto Pe´rez Rodri´guez ◽  
Rafael Garci´a Illescas
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Performance Test ◽  
Operating Conditions ◽  
Technical Requirements ◽  
Requirements Specifications ◽  
Commercial Operation ◽  
International Regulations ◽  
Operational Tests

In order to evaluate the performance of new turbo gas power plants for putting in commercial operation, it was necessary to supervise, test and, if so the case, to approve the works of commissioning, operational and acceptance of all equipments and systems that constitute the power plant. All this was done with the aim of guaranteeing the satisfactory operation of these elements to accomplish the function for which they were developed. These activities were conducted at the request of the customer to confirm and observe that the evidence of the tests was carried out according to the specifications and international regulations. The putting into commercial operation activities were done in collaboration with the supplier and manufacturer of equipment, the client and the institution responsible for certification and approval of the plant. All this in a logical and chronological order for the sequence of commissioning tests, operation and acceptance. Commissioning tests were carried out on-site at normal operating conditions, according to the design and operation needs of each power plant of a group of 14. Once the commissioning tests were completely executed and in a satisfactory manner, operational tests of the plants were developed. This was done by considering that they must operate reliable, stable, safe and automatically, satisfying at least, one hundred hours of continuous operation at full load. After evaluating the operational capacity of the machine, it was necessary to determinate the quality of the plant by carrying out a performance test. Finally, it was verified if every unit fulfills the technical requirements established in terms of heat capacity of the machine, noise levels and emissions. As a result of this process, it is guaranteed to the customer that the turbo gas power plants, their systems and equipments, satisfy the requirements, specifications and conditions in agreement with the supplier and manufacturers referring to the putting into commercial operation of the plant.

scholarly journals ReCAP: Feasibility and Effectiveness of a Pilot Program to Facilitate Quality Improvement Learning in Oncology: Experience of the American Society of Clinical Oncology Quality Training Program

2016 ◽  
Vol 12 (2) ◽  
pp. 177-177 ◽  
Author(s):  
Arif H. Kamal ◽  
Doris Quinn ◽  
Timothy D. Gilligan ◽  
Barbara Corning Davis ◽  
Carole K. Dalby ◽  
...  
Keyword(s):  
Quality Improvement ◽  
Training Program ◽  
Real Life ◽  
Pilot Project ◽  
Early Adopters ◽  
High Participation ◽  
American Society ◽  
Structured Program

CONTEXT AND QUESTION ASKED: Improving quality of oncology delivery is an important responsibility for busy oncology practices. Is it feasible to construct a training program for oncology professionals to teach quality improvement that is applicable to practice? SUMMARY ANSWER: Using a longitudinal, project-based program with a mix of in-person and distance-learning components, the ASCO Quality Training Program is a highly feasible method to facilitate quality improvement learning in oncology. METHODS: The ASCO Quality Training Program (QTP) consisted of three in-person Learning Sessions and four phases: pre-work, planning, implementation, and sustain and spread. We measured two primary outcomes: program feasibility and effectiveness. BIAS, CONFOUNDING FACTOR(S), DRAWBACKS: Although we observed high participation, satisfaction, and applicability of content to the needs of the oncology learners, it should be noted that this represents a small, pilot project. REAL-LIFE IMPLICATIONS: Even busy oncology clinicians find a structured program to learn and practice quality improvement skills valuable. Conclusions regarding long-term applicability effectiveness and feasibility among non-early adopters require further study.

Sign in / Sign up

Export Citation Format

Share Document