scholarly journals Gas Turbine Driven Centrifugal Compressors for Gas Storage and Withdrawal Applications

1986 ◽  
Author(s):  
Horst Hornberger ◽  
Albrecht Wockenfuss ◽  
Klaus D. Schmidt
Keyword(s):  
High Reliability ◽  
Gas Storage ◽  
Primary Energy ◽  
Gas Compression ◽  
Wide Range ◽  
Winter Time ◽  
Discharge Pressure ◽  
Summer Time ◽  
Gas Fields ◽  
Gas Supply

The increasing acceptance of natural gas as primary energy in different market segments and the variance in consumption between the seasons require more and more buffer storage capacity, because of contracted constant gas supply quantities. The surplus gas becoming available during the summer time can be stored and withdrawn during the winter time for covering peak demands. Based on these facts, the gas distribution companies utilize exploited gas fields for gas storage by drilling additional wells and installing gas compression facilities. Such a compression duty with a wide range in flow and discharge pressure requires a great flexibility of the compression equipment, including high reliability and availability during operation periods.

Spatiotemporal modelling of induced seismicity with a stress-based statistical approach applied to different production sites

2020 ◽  
Author(s):  
Gudrun Richter ◽  
Sebastian Hainzl ◽  
Peter Niemz ◽  
Francesca Silverii ◽  
Torsten Dahm ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Induced Seismicity ◽  
Gas Storage ◽  
Spatiotemporal Pattern ◽  
Model Parameters ◽  
Storage Site ◽  
Data Set ◽  
Wide Range ◽  
Stress Changes ◽  
Gas Fields

<p>In the framework of the Geo:N project SECURE (Sustainable dEployment and Conservation of Underground Reservoirs and Environment) we developed a Python software toolbox to model the rate and distribution of seismicity induced by anthropogenic stress changes at various production sites (gas production, hydrofracturing, gas storage). This toolbox tests different frictional behavior of the underground (linear or rate-and-state stressing rate dependent, critically or subcritically prestressed faults) and takes into account the uncertainties of the production site parameters. The knowledge on the location and orientation of pre-existing faults can be considered as well. Model parameters are estimated by fitting the model to recorded historical seismicity using a maximum likelihood approach. We discuss applications at conventional gas fields, hydraulic fracturing experiments and an aquifer gas storage site, covering a wide range of spatial and temporal scales of induced seismicity in different settings and for different production schemes. This enables to investigate the underlying physical processes by the comparison of the different models. Additionally, the model parameters are linked to frictional material properties and the best performing model can be used to forecast the seismicity rates in space and time with their uncertainties according to the production plans.</p><p>Induced seismicity at gas fields in the Northern Netherlands and in Germany have similar tectonic settings but very different extents, depths and production histories. The data set of two sites are compared which both show a large delay of the first recorded seismicity after the start of production. Using our model we can reproduce the long delay for both sites. Thanks to the long and detailed data set we successfully reproduce the spatiotemporal pattern of the seismicity of one site, whereas the limited number of seismic events result in large uncertainties for the other site. In the comparative testing of the models the critically prestressed rate-and-state model performs best. This means that the complete stressing history influences the resulting seismicity. We also applied the model to a hydraulic fracturing experiment in granite comparing data sets for different fracturing methods and different phases of a stimulation experiment. Hundreds of microearthquakes are localized in a volume of roughly 15x15m with increasing number of events for later refraction stages indicating the growth of rock fracturing. A third application is run for a gas storage in an aquifer layer, which is loaded by injection and production operations. Here the proportion of the tectonic versus the anthropogenic induced seismicity is investigated analyzing the varying number of small local earthquakes in the region.</p>

scholarly journals Gas Turbine Compressor Unit Application in Sour Gas Field Operation

1986 ◽  
Author(s):  
Klaus D. Schmidt ◽  
Werner Scholz ◽  
Hartmut Schlüter
Keyword(s):  
Treatment Plant ◽  
Primary Energy ◽  
West Germany ◽  
Gas Field ◽  
Gas Treatment ◽  
Supply Pressure ◽  
Gas Compression ◽  
Gas Turbine Compressor ◽  
Gas Fields ◽  
Sour Gas

The use of sour gas as primary energy requires constant supply pressure and flow to the gas treatment plant as well as to the pipeline distribution network and consumers. During exploitation of gas fields, when the well head pressure and flow decreases, production continues at increased cost. Application of gas compression equipment is required for continuation of supply pressure and flow to the sour gas treatment plant and to customer connection flanges. The design and layout of sour gas compression equipment has to guarantee high operational availability and reliability for continuous duty. To properly select equipment for sour gas applications, including the compressor, its driver and auxiliary and ancillary systems, the specific requirements and standards have to be taken into consideration. This paper will report about a situation in the sour gas fields in the northern part of West Germany and will describe the design objectives, station layout and equipment selection for a sour gas compressor station including operating experiences.

Design and Implement of Automatic Control System of the Campus Ringer

2012 ◽  
Vol 241-244 ◽  
pp. 1113-1117
Author(s):  
Gui Sheng Fang
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Automatic Control System ◽  
High Reliability ◽  
Current System ◽  
College English ◽  
Test Mode ◽  
Text Display ◽  
Winter Time ◽  
Summer Time

According to the control requirements of campus ringers, a PLC-based automatic control system is realized by using the real time clock function provided by S7-200 CPU224 PLC and the friendly human-computer interaction function provided by TD400 text display. The control system can automatically judge the ringing work mode by the current system time of PLC, that is the summer time ringing mode and the winter time ringing mode. The user can also choose other work modes, such as the college English test mode and the computer grade test mode by pushing the button of the text display. In this paper the composition of the control system, the working principle and the designs of hardware and software are introduced. The system has advantages of friendly interface, simple operation, convenient maintenance, high reliability, strong anti interference ability, which makes it popularize.

scholarly journals The Comprehensive Autistic Trait Inventory (CATI): development and validation of a new measure of autistic traits in the general population

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Michael C. W. English ◽  
Gilles E. Gignac ◽  
Troy A. W. Visser ◽  
Andrew J. O. Whitehouse ◽  
James T. Enns ◽  
...  
Keyword(s):  
Factor Analysis ◽  
General Population ◽  
Measurement Invariance ◽  
High Reliability ◽  
Predictive Ability ◽  
Autistic Traits ◽  
Autism Spectrum ◽  
Autism Spectrum Quotient ◽  
Sensory Sensitivity ◽  
Wide Range

Abstract Background Traits and characteristics qualitatively similar to those seen in diagnosed autism spectrum disorder can be found to varying degrees in the general population. To measure these traits and facilitate their use in autism research, several questionnaires have been developed that provide broad measures of autistic traits [e.g. Autism-Spectrum Quotient (AQ), Broad Autism Phenotype Questionnaire (BAPQ)]. However, since their development, our understanding of autism has grown considerably, and it is arguable that existing measures do not provide an ideal representation of the trait dimensions currently associated with autism. Our aim was to create a new measure of autistic traits that reflects our current understanding of autism, the Comprehensive Autism Trait Inventory (CATI). Methods In Study 1, 107 pilot items were administered to 1119 individuals in the general population and exploratory factor analysis of responses used to create the 42-item CATI comprising six subscales: Social Interactions, Communication, Social Camouflage, Repetitive Behaviours, Cognitive Rigidity, and Sensory Sensitivity. In Study 2, the CATI was administered to 1068 new individuals and confirmatory factor analysis used to verify the factor structure. The AQ and BAPQ were administered to validate the CATI, and additional autistic participants were recruited to compare the predictive ability of the measures. In Study 3, to validate the CATI subscales, the CATI was administered to 195 new individuals along with existing valid measures qualitatively similar to each CATI subscale. Results The CATI showed convergent validity at both the total-scale (r ≥ .79) and subscale level (r ≥ .68). The CATI also showed superior internal reliability for total-scale scores (α = .95) relative to the AQ (α = .90) and BAPQ (α = .94), consistently high reliability for subscales (α > .81), greater predictive ability for classifying autism (Youden’s Index = .62 vs .56–.59), and demonstrated measurement invariance for sex. Limitations Analyses of predictive ability for classifying autism depended upon self-reported diagnosis or identification of autism. The autistic sample was not large enough to test measurement invariance of autism diagnosis. Conclusions The CATI is a reliable and economical new measure that provides observations across a wide range of trait dimensions associated with autism, potentially precluding the need to administer multiple measures, and to our knowledge, the CATI is also the first broad measure of autistic traits to have dedicated subscales for social camouflage and sensory sensitivity.

scholarly journals Research on Injection-Production Capability and Seepage Characteristics of Multi-Cycle Operation of Underground Gas Storage in Gas Field—Case Study of the Wen 23 Gas Storage

Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3829
Author(s):  
Jie Zhang ◽  
Feifei Fang ◽  
Wei Lin ◽  
Shusheng Gao ◽  
Yalong Li ◽  
...  
Keyword(s):  
Transition Zone ◽  
Pore Volume ◽  
High Speed ◽  
Gas Storage ◽  
Production Flow ◽  
Underground Gas Storage ◽  
Gas Recovery ◽  
Gas Drive ◽  
Gas Fields ◽  
Water Gas

With the increasing energy demands of current modern society, underground gas storage (UGS) in gas fields is the most popular type of UGS used to meet the seasonal variation of gas consumption. However, compared with gas fields, UGS in gas fields has the characteristics of periodic high-speed injection and production of exploitation modes and operation rules, which causes the rules of gas-water seepage and utilization of reserves to be more particular and complicated. In this paper, based on Wen 23 gas storage, the rules of multicycle injection and production flow and the utilization of UGS pore volume were investigated. The experimental results showed that variation in porosity and permeability caused by injection and production pressure changes in Wen 23 gas storage can be neglected. The pore volume of gas storage and the degree of gas recovery increased gradually in the pre-UGS gas zone, which was higher than that of reservoirs. In the initial stage of UGS operation, the pore volume of gas storage and the degree of gas recovery were low in the gas-drive-water gas zone as a result of water invasion during the process of reservoir exploitation. During operation of multicycle high-speed injection and production, the seepage conditions in the gas-drive-water gas zone gradually improved. The higher the reservoir permeability, the greater increases in pore volume and degree of gas recovery. In the gas-water transition zone, gas and water were reciprocated and displaced with the multicycle injection-production of UGS, resulting in the gradual deterioration of pore volume and gas recovery, which remained stable at a low value. The negative effects of reservoir heterogeneity on the effective utilization of UGS occurred in the gas-water transition zone. These findings may contribute to a better understanding of the rules of multicycle injection and production flow and utilization of UGS to optimize the injection-production efficiency of Wen 23 gas storage.

The Research of GPRS-Based Remote Fault Monitoring System for CNC Machine Tools

2011 ◽  
Vol 328-330 ◽  
pp. 393-397
Author(s):  
Ming Liang Wu ◽  
Xiao Bing Wang ◽  
Shu Rong Yu
Keyword(s):  
Monitoring System ◽  
Communication Networks ◽  
Remote Monitoring ◽  
Data Transfer ◽  
High Reliability ◽  
Fast Response ◽  
Cnc Machine Tools ◽  
Cnc Machine ◽  
Remote Monitoring System ◽  
Wide Range

Based on GPRS network remote monitoring system which uses its two-way transmission performance, can easily monitor various electrical equipments and get information. Compare with the past remote monitoring systems, the system has the advantage of flexible networking, convenient, wide range of data transmission, high reliability, fast response time, and has great significance and value of research in CNC machine tool system with upgrade GPRS in the mobile communication networks, data services expand and data transfer capabilities.

scholarly journals A systematic comparison and reliability analysis of formal measures of sentence acceptability

2019 ◽  
Author(s):  
Steven Langsford ◽  
Andrew T Hendrickson ◽  
Amy Perfors ◽  
Lauren Kennedy ◽  
Danielle Navarro
Keyword(s):  
High Reliability ◽  
Significant Degree ◽  
Response Styles ◽  
The Other ◽  
Likert Scales ◽  
Wide Range ◽  
Acceptability Judgments ◽  
Test Retest Reliability ◽  
Item Effects ◽  
Do So

Understanding and measuring sentence acceptability is of fundamental importance for linguists, but although many measures for doing so have been developed, relatively little is known about some of their psychometric properties. In this paper we evaluate within- and between-participant test-retest reliability on a wide range of measures of sentence acceptability. Doing so allows us to estimate how much of the variability within each measure is due to factors including participant-level individual differences, sample size, response styles, and item effects. The measures examined include Likert scales, two versions of forced-choice judgments, magnitude estimation, and a novel measure based on Thurstonian approaches in psychophysics. We reproduce previous findings of high between-participant reliability within and across measures, and extend these results to a generally high reliability within individual items and individual people. Our results indicate that Likert scales and the Thurstonian approach produce the most stable and reliable acceptability measures and do so with smaller sample sizes than the other measures. Moreover, their agreement with each other suggests that the limitation of a discrete Likert scale does not impose a significant degree of structure on the resulting acceptability judgments.

Microgrid Model on Homer Software

2021 ◽  
Vol 9 (VI) ◽  
pp. 757-760
Author(s):  
Mohd Ahamad
Keyword(s):  
Power Generation ◽  
Power Electronics ◽  
Life Cycle Cost ◽  
Low Voltage ◽  
High Reliability ◽  
Low Cost ◽  
Local Area ◽  
New Paradigm ◽  
Power Sources ◽  
Wide Range

A new concept in power generation is a microgrid. The Microgrid concept assumes a cluster of loads and microsources operating as a single controllable system that provides power to its local area. This concept provides a new paradigm for defining the operation of distributed generation. The microsources of special interest for MGs are small (<100-kW) units with power electronic interfaces. These sources are placed at customers sites. They are low cost, low voltage and have a high reliability with few emissions. Power electronics provide the control and flexibility required by the MG concept. A properly designed power electronics and controllers insure that the MG can meet the needs of its customers as well as the utilities. The goal of this project is to build a complete model of Microgrid including the power sources, their power electronics, and a load and mains model in THE HOMER. The HOMER Micropower Optimization Model is a computer model developed by the U.S. National Renewable Energy Laboratory (NREL) to assist in the design of micropower systems and to facilitate the comparison of power generation technologies across a wide range of applications. HOMER models a power system’s physical behavior and its life-cycle cost, which is the total cost of installing and operating the system over its life span. HOMER allows the modeler to compare many different design options based on their technical and economic merits. It also assists in understanding and quantifying the effects of uncertainty or changes in the inputs.

Advanced Microelectronics Packaging Solutions for Miniaturized Medical Devices

2013 ◽  
Vol 2013 (DPC) ◽  
pp. 001963-001976
Author(s):  
Rabindra Das ◽  
Steven Rosser ◽  
Frank Egitto
Keyword(s):  
Flip Chip ◽  
New Technologies ◽  
High Reliability ◽  
Present Report ◽  
Flexible Substrate ◽  
System Level ◽  
Organic Substrates ◽  
Internal Layers ◽  
Microelectronics Packaging ◽  
Wide Range

The wide range of applications for medical electronics drives unique requirements that can differ significantly from commercial & military electronics. To accomplish this, new packaging structures need to be able to integrate more dies with greater function, higher I/O counts, smaller die pad pitches, and high reliability, while being pushed into smaller and smaller footprints. As a result, the microelectronics industry is moving toward alternative, innovative approaches as solutions for squeezing more function into smaller packages. In the present report, key enablers for achieving reduction in size, weight, and power (SWaP) in electronic packaging for a variety of medical applications are discussed. Advanced microelectronics packaging solutions with embedded passives are enabling SWaP reductions. Implementation of these solutions has realized up to 27X reduction in physical size for existing PWB assemblies, with significant reductions in weight. Shorter interconnects can also reduce or eliminate the need for termination resistors for some net topologies. Successful miniaturized products integrate the following design techniques and technologies: component footprint reduction, thin high density interconnects substrate technologies, I/O miniaturization and IC assembly capabilities. This paper presents fabrication and electrical characterization of embedded actives and passives on organic multilayered substrates. We have designed and fabricated several printed wiring board (PWB) and flip-chip package test vehicles focusing on embedded chips, resistors, and capacitors. Embedded passive technology further enhances miniaturization by enabling components to be moved from the surface of the substrate to its internal layers. The use of thin film resistor material allows creating individual miniaturized buried resistors. These resistors provide additional length and width reduction with negligible increases to the overall substrate and module (SiP) height. Resistor values can vary from 5 ohm to 50 Kohm with tolerances from 5 to 20% and areas as small as 0.2 mm2. The embedded resistors can be laser trimmed to a tolerance of &lt;5% for applications that require tighter tolerance. The electrical properties of embedded capacitors fabricated from polymer-ceramic nanocomposites showed a stable capacitance and low loss over a wide frequency and temperature range. A few test vehicles were assembled to do system level analysis. Manufacturing methods and materials for producing advanced organic substrates and flex along with ultra fine pitch assemblies are discussed. A case study detailing the fabrication of a flexible substrate for use in an intravascular ultrasound (IVUS) catheter demonstrates how the challenges of miniaturization are met. These challenges include use of ultra-thin polymer films, extreme fine-feature circuitization, and assembly processes to accommodate die having reduced die pad pitch. In addition, new technologies for embedding a variety of active chips are being developed. A variety of active chips, including a chip having dimensions of one millimeter square, have been embedded and electrically connected to develop high performance packages.

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