Academic literature on the topic 'Tone clusters Analysis'
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Journal articles on the topic "Tone clusters Analysis"
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Watanabe, Tetsuo, and Masashi Suzuki. "Analysis of the Audiogram Shape in Patients with Idiopathic Sudden Sensorineural Hearing Loss using a Cluster Analysis." Ear, Nose & Throat Journal 97, no. 6 (June 2018): 2–6. http://dx.doi.org/10.1177/014556131809700706.
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We performed a cluster analysis to classify the audiogram shape in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). We also investigated whether the audiogram shape is a prognostic indicator in the management of ISSNHL. A total of 115 inpatients with ISSNHL treated between 2001 and 2010 were analyzed. The data collected included age, sex, duration of hearing loss at the time of treatment, and the presence or absence of tinnitus, vertigo, diabetes, nystagmus, and canal paresis. A hierarchical cluster analysis was performed using the hearing threshold for each frequency on audiograms as variables. A logistic regression model was used for the prognostic analysis. The audiogram shape was classified into four clusters: (1) crossing horizontally pattern of all tones; (2) up-sloping pattern of low-tone loss; (3) deaf pattern; and (4) down-sloping pattern of high-tone loss. The age of the patient, presence of canal paresis, and audiogram shape showed statistically significant relationships with hearing improvement. The audiogram shape based on the cluster analysis demonstrated a significant relationship with hearing improvement in patients with ISSNHL. Further studies are needed to elucidate the underlying etiology of each audiogram shape.
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Hyun, Myung Han, Jun Hyuk Kang, Sunghwan Kim, Jin Oh Na, Cheol Ung Choi, Jin Won Kim, Eung Ju Kim, et al. "Patterns of Circadian Variation in 24-Hour Ambulatory Blood Pressure, Heart Rate, and Sympathetic Tone Correlate with Cardiovascular Disease Risk: A Cluster Analysis." Cardiovascular Therapeutics 2020 (September 22, 2020): 1–9. http://dx.doi.org/10.1155/2020/4354759.
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To investigate whether specific time series patterns for blood pressure (BP), heart rate (HR), and sympathetic tone are associated with metabolic factors and the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). A total of 989 patients who underwent simultaneous 24-hour ambulatory BP and Holter electrocardiogram monitoring were enrolled. The patients were categorized into sixteen groups according to their circadian patterns using the consensus clustering analysis method. Metabolic factors, including cholesterol profiles and apolipoprotein, were compared. The 10-year ASCVD risk was estimated based on the Framingham risk model. Overall, 16 significant associations were found between the clinical variables and cluster groups. Age was commonly associated with all clusters in systolic BP (SBP), diastolic BP (DBP), HR, and sympathetic tone. Metabolic indicators, including diabetes, body mass index, total cholesterol, high-density lipoprotein, and apolipoprotein, were associated with the four sympathetic tone clusters. In the crude analysis, the ASCVD risk increased incrementally from clusters 1 to 4 across SBP, DBP, HR, and sympathetic tone. After adjustment for multiple variables, however, only sympathetic tone clusters 3 and 4 showed a significantly high proportion of patients at high risk (≥7.5%) of 10-year ASCVD (odds ratio OR=5.90, 95% confidential interval CI=1.27–27.46, and P value = 0.024 and OR=15.28, 95% CI=3.59–65.11, and P value < 0.001, respectively). Time series patterns of BP, HR, and sympathetic tone can serve as an indicator of aging. Circadian variations in sympathetic tone can provide prognostic information about patient metabolic profiles and indicate future ASCVD risk.
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Tay, Dennis. "A Computerized Text and Cluster Analysis Approach to Psychotherapy Talk." Language and Psychoanalysis 9, no. 1 (March 7, 2020): 4–25. http://dx.doi.org/10.7565/landp.v9i1.1701.
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This paper illustrates an analytical approach combining LIWC, a computer text-analytic application, with cluster analysis techniques to explore ‘language styles’ in psychotherapy across sessions in time. It categorizes session transcripts into distinct clusters or styles based on linguistic (di)similarity and relates them to sessional progression, thus providing entry points for further qualitative exploration. In the first step, transcripts of four illustrative therapist-client dyads were scored under ten LIWC variables including ‘analytic thinking’, ‘clout’, ‘authenticity’, ‘emotional tone’, and pronoun types. In the next step, agglomerative hierarchical clustering uncovered distinct session clusters that are differently distributed in each dyad. The relationships between these clusters and the chronological progression of sessions were then further discussed in context as contrastive exemplars. Applications, limitations and future directions are highlighted.
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Cutting, Court B. "Microtonal Analysis of "Blue Notes" and the Blues Scale." Empirical Musicology Review 13, no. 1-2 (January 17, 2019): 84. http://dx.doi.org/10.18061/emr.v13i1-2.6316.
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Microtonal evaluation of blue notes in the early blues scale by empirical pitch measurement and statistical characterization has not yet been performed in existing research. To address this, fifteen recorded classic blues performances by acknowledged early masters of the blues were studied. Computer based methods were used to collect the audio frequencies of note samples from each performance. Each note had its frequency ratio with respect to the average tonic tone for the performance converted to microtonal cents format. Cluster analysis was performed on these note collections to identify individual note clusters. The fourth and fifth were clearly identified. Three principal "blue note" clusters were isolated with means of 319.1, 582.8, and 1037.9 cents. These values corresponded closely to the harmonic half diminished seventh chord (i.e. 1, ♭3, ♭5, ♭7 with harmonics 5:6:7:9). The "neutral" third was confirmed to occur in this sample. A similar blending of the perfect fourth and tritone was demonstrated in this study. The flat 7th presented as three separate clusters. Several clusters idiosyncratic to individual performers were also identified. Findings are discussed with regards to the array of theories proposed to explain the blues.
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Huang, Alan Guoming, Hongping Tan, and Russ Wermers. "Institutional Trading around Corporate News: Evidence from Textual Analysis." Review of Financial Studies 33, no. 10 (January 8, 2020): 4627–75. http://dx.doi.org/10.1093/rfs/hhz136.
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Abstract We examine institutional trading surrounding corporate news by combining a comprehensive database of newswire releases on U.S. firms with a high-frequency database of institutional trades. To identify the ability of institutions to predict or quickly interpret news, we form “news clusters” of related news about a particular firm that occurs in rapid succession. We find that institutions chiefly trade on the tone of news directly after the earliest news release in a cluster, and such news-motivated trading predicts returns over the following weeks. Our results suggest that institutional investors contribute to price efficiency through the speedy interpretation of public information.
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Kourtidis, Dimitrios, Željko Šević, and Prodromos Chatzoglou. "Mood and stock returns: evidence from Greece." Journal of Economic Studies 43, no. 2 (May 9, 2016): 242–58. http://dx.doi.org/10.1108/jes-09-2014-0158.
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Purpose – The purpose of this paper is to examine the effect of investors’ emotional state (mood) on their trading behaviour and performance. Design/methodology/approach – A sample from a representative survey of 328 Greek individual investors has been used to empirically test the validity of the proposed associations. An iterative data collection process was followed, where individual investors had to complete a questionnaire every time they were trading in the Athens Stock Exchange, for a period of ten months. Exploratory factor analysis was first used to analyse the data set, followed by cluster analysis (to identify investor profiles based on differences in their mood). Findings – Two clusters have been identified. The first cluster profile includes investors with high score of positive mood (thus, high energetic arousal and hedonic tone, low tense arousal and anger frustration), while the second profile consists of investors with negative mood (low energetic arousal and hedonic tone, high tense arousal and anger frustration). The comparison between the two profiles has shown that investors with positive mood achieve higher stock returns than investors with negative mood. Originality/value – To the best of the authors’ knowledge there is no other similar study.
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Casali, Roderic F. "NCs in Moghamo prenasalized onsets or heterosyllabic clusters." Studies in African Linguistics 24, no. 2 (June 15, 1995): 151–65. http://dx.doi.org/10.32473/sal.v24i2.107406.
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This paper is concerned with the analysis of nasal-plus-oral-stop sequences in Moghamo, a Grassfields Bantu language of Cameroon. Although Stallcup [1978] tentatively analyzed these sequences as heterosyllabic clusters, the evidence suggests that they are actually prenasalized syllable onsets. First, the distribution of NCs closely parallels that of unambiguous onsets: they occur both initially and medially in words of several grammatical categories. Instances of unambiguous heterosyllabic clusters, by contrast, are rare. Second, while the nasal portion of noun-initial NCs was historically a prefix, it appears to be part of the root synchronically. Third, the nasal portion of an Niger-Congo does not appear to be phonologically tone-bearing. Finally, the contention that NCs are on-sets is supported by native speaker intuitions.
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Kozyavkina, Nataliya, Nataliya Voronych-Semchenko, Yuliya Vovchyna, Walery Zukow, and Igor Popovych. "Autonomic and endocrine accompaniments of quantitative-qualitative blood pressure clusters in patients of Truskavets’ spa." Journal of Education, Health and Sport 10, no. 7 (July 31, 2020): 465–77. http://dx.doi.org/10.12775/jehs.2020.10.07.048.
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Background. Earlier we showed that profile patients of Truskavets’ spa are characterized by a wide range of blood pressure (BP) - from low norm to arterial hypertension III that correspond to the hemodynamics parameters. The purpose of this study is to clarify the autonomic and endocrine accompaniments of quantitative-qualitative BP clusters in the same contingent. Materials and methods. Under an observations were 44 patients with chronic pyelonephritis and cholecystitis in the phase of remission. Testing was performed twice - on admission and after 7-10 days of standard balneotherapy. The main object of the study was BP (tonometer “Omron M4-I”, Netherlands). The parameters of HRV ("CardioLab+HRV", Ukraine), plasma levels of Cortisol, Aldosterone, Testosterone, Triiodothyronine and Calcitonin (ELISA) as well as Ca-P marker of parathyroid hormone were determined. Results. In order to identify among the registered parameters, those for which the BP clusters differ from each other, a discriminant analysis was performed. The program forward stepwise included in the discriminant model 29 parameters. The most informative among them are HRV-markers of sympathetic tone and sympathetic-vagal balance as well as testosterone and cortisol, whose levels are maximal in patients with hypertension II, while minimal in patients with low norm BP, on the one hand, and markers of vagal tone and Kerdoe vegetative index, the levels of which are polar, on the other hand. The accuracy of patient classification is 98,9%. Conclusion. Autonomic and endocrine accompaniments of quantitative-qualitative blood pressure clusters corresponding to the existing ideas about the regulation of blood pressure.
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Pritchard, Harry A. T., Paulo W. Pires, Evan Yamasaki, Pratish Thakore, and Scott Earley. "Nanoscale remodeling of ryanodine receptor cluster size underlies cerebral microvascular dysfunction in Duchenne muscular dystrophy." Proceedings of the National Academy of Sciences 115, no. 41 (September 4, 2018): E9745—E9752. http://dx.doi.org/10.1073/pnas.1804593115.
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Duchenne muscular dystrophy (DMD) results from mutations in the gene encoding dystrophin which lead to impaired function of skeletal and cardiac muscle, but little is known about the effects of the disease on vascular smooth muscle cells (SMCs). Here we used the mdx mouse model to study the effects of mutant dystrophin on the regulation of cerebral artery and arteriole SMC contractility, focusing on an important Ca2+-signaling pathway composed of type 2 ryanodine receptors (RyR2s) on the sarcoplasmic reticulum (SR) and large-conductance Ca2+-activated K+ (BK) channels on the plasma membrane. Nanoscale superresolution image analysis revealed that RyR2 and BKα were organized into discrete clusters, and that the mean size of RyR2 clusters that colocalized with BKα was larger in SMCs from mdx mice (∼62 RyR2 monomers) than in controls (∼40 RyR2 monomers). We further found that the frequency and signal mass of spontaneous, transient Ca2+-release events through SR RyR2s (“Ca2+ sparks”) were greater in SMCs from mdx mice. Patch-clamp electrophysiological recordings indicated a corresponding increase in Ca2+-dependent BK channel activity. Using pressure myography, we found that cerebral pial arteries and parenchymal arterioles from mdx mice failed to develop appreciable spontaneous myogenic tone. Inhibition of RyRs with tetracaine and blocking of BK channels with paxilline restored myogenic tone to control levels, demonstrating that enhanced RyR and BK channel activity is responsible for the diminished pressure-induced constriction of arteries and arterioles from mdx mice. We conclude that increased size of RyR2 protein clusters in SMCs from mdx mice increases Ca2+ spark and BK channel activity, resulting in cerebral microvascular dysfunction.
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Lin, Xuqin. "Perplexity and Predicament: A Corpus Stylistic Analysis of A Summer Bird-Cage." Arab World English Journal For Translation and Literary Studies 5, no. 1 (February 15, 2021): 159–76. http://dx.doi.org/10.24093/awejtls/vol5no1.11.
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This paper aims to explore the text style of Margaret Drabble’s novel A Summer Bird-Cage. Specifically, it is intended to scrutinize how Drabble’s language style vivifies her representation of some women characters’ perplexity and predicament when they are confronted with problems related to value orientations and lifestyles. The present paper’s significance lies in a methodological breakthrough and resultant interdisciplinary insights. To achieve the main aims specified above, this paper will explore the following research question: stylistically, how some lexical categories such as nouns, verbs, and clusters are related to the spatio-temporal order of the novel and to its discourse prosodies or “tone of characters” speeches. As a whole, this study is situated in a research context where previous and many current studies of A Summer Bird-Cage are primarily qualitative. To complement them, this paper embodies mixed methods research, featuring in a computer-aided, data-based, corpus stylistic approach to the style in Drabble’s novel. Based on a multi-layered investigation of Drabble’s language use and a close corpus stylistic analysis of it, this paper obtains some interesting findings as follows. First, some young, educated British women’s complicated psychological experiences are thematized via narratorial introspection that centers around characters’ processing of mind. Second, the tone of the women characters’ speeches and the underlying attitude to some important issues are often negative, indicative of the women characters’ bewilderment. In short, this paper adopts a corpus stylistic approach to thematic studies and character analysis as a contribution to the body of specialized knowledge of Drabble’s art of fiction.
Dissertations / Theses on the topic "Tone clusters Analysis"
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Kharitonov, Arsentiy. "Unorthodox Pianism and Its Unexpected Consequences: A Performance Guide to Leo Ornstein's Seventeen Waltzes." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc984226/.
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Leo Ornstein's most significant piano oeuvre, the Seventeen Waltzes, stand out as a unique example of a pianism as a foundation for the composer's musical thoughts. The purpose of this document is to provide musical and technical suggestions based on Ornstein's pianistic patterns, which will help pianists understand the composer's complex writing and form a coherent interpretation. The guide covers the main avant-garde musical devices used by Ornstein such as tone clusters, polymeter, and polyrhythm. A comparison process within the collection will help performers to address Ornstein's unmarked waltzes by underlining the composer's similar ideas and traits.
Books on the topic "Tone clusters Analysis"
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1955-, Wang Yan, ed. Zhongguo jiao tong yun shu chan ye de gai ge yu fa zhan: Reform and development on Chinese transportation industry. Beijing Shi: Jing ji guan li chu ban she, 2010.
Find full textConference papers on the topic "Tone clusters Analysis"
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Alajmei, Shabeeb, and Jennifer Miskimins. "Limited Entry Perforation Configurations Effect on Proppant Transport and Distribution in Fresh Water." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204163-ms.
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Abstract Proppant transport in horizontal wellbores has received significant industry focus over the past decade. One of the most challenging tasks in the hydraulic fracturing of a horizontal well is to predict the proppant concentration that enters each perforation cluster within the same stage. The main objective of this research is to investigate the effect of different limited-entry perforation configurations on proppant transport, settling, and distribution across different perforation clusters in multistage horizontal wells. To simulate a fracturing stage in a horizontal wellbore, a laboratory-based 30-foot horizontal clear apparatus with three perforation clusters is used. Fresh water (~1 cp) is utilized as the carrier fluid to transport the proppant. This research incorporates the effect of testing three different injection rates each at four different proppant concentrations on proppant transport. Different limited-entry perforation configurations are also used to test the perforation effect on proppant transport using similar injection rates and proppant concentrations for the same proppant size. The proppant is mixed with fresh water in a 200-gallon tank for at least 10 minutes to ensure the consistency of the slurry mixture. The mixture is then injected into the transparent horizontal wellbore through a slurry pump. This laboratory apparatus also includes a variable frequency drive, a flow meter, and two pressure transducers located right before the first two perforation clusters. Sieve analysis is conducted to understand the ability of fresh water to carry bigger particles of the mixture at different injection rates, proppant concentrations, and perforation configurations. The results show different fluid and proppant distributions occur when altering the perforation configurations, injection rates, and proppant concentrations. The effect of gravity is extreme when using a limited entry configuration at each cluster (1 SPF) located at the bottom of the pipe, especially at low injection rates, resulting in uneven proppant distribution with a heal-biased distribution. However, even proppant distribution is observed by changing the limited entry perforation configuration to the top of the horizontal pipe at similar injection rates and low proppant concentration. Increasing the proppant concentration reduces the void spaces between the particles and pushes them away toward the toe cluster. Even proppant distribution is also observed across the three perforation clusters when using high flow rates and a 2 SPF perforation configuration located at both the top and the bottom of the pipe. The results of the sieve analyses show different size distributions of the settled and exited proppant through different perforations and clusters. This illustrates the ability of fresh water to transport different percentages of different proppant sizes to different perforations and clusters within a single stage. Frequently, the injected proppant is assumed to be distributed evenly across the perforation clusters and that the distribution of fluid and proppant is identical. However, this research adds data to the portfolio that this assumption is generally not valid. Additionally, the distribution of the transported proppant is observed to be different across individual clusters and different perforations within each cluster. Such information is beneficial to understanding transport in horizontal, multi-stage completions and how such impacts the overall treatment efficiency, especially when employing limited-entry perforation techniques.
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Sinkov, Konstantin, Xiaowei Weng, and Olga Kresse. "Modeling of Proppant Distribution During Fracturing of Multiple Perforation Clusters in Horizontal Wells." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204207-ms.
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Abstract Uniformity of proppant distribution among multiple perforation clusters affects treatment efficiency in multistage fractured wells stimulated using the plug-and-perf technique. Multiple physical phenomena taking place in the well and perforation tunnels can cause uneven proppant distribution among multiple clusters. The problem has been studied in the recent years with experimental and computational fluid dynamics (CFD) methods, which provide useful insights but are impractical for routine designs. Simplified models that incorporated the proppant transport efficiency (PTE) correlation derived from the CFD results in a hydraulic fracture model have been also presented in literature. In this paper, we present a numerical model that simulates the transient proppant slurry flow in the wellbore, considering proppant transport and settling including bed formation, rate- and concentration-dependent pressure drop, PTE, and dynamic pressure coupling with the hydraulic fractures. The model is efficient and is designed to be an independent wellbore transport model so it can be integrated with any fracture models, including fully 3D and/or complex fracture network models, for practical design optimization. The model predictions are compared and found to agree with previously published studies. Parametric studies demonstrate sensitivity of proppant distribution to grain size, fluid viscosity, and pumping rate for fixed perforation designs. Analysis of the simulation results shows that the dominant cause of uneven proppant distribution is proppant inertia. Possible slurry stratification is less important, except for the cases with relatively low flow rates and near toe clusters. Accordingly, proppant distribution is less sensitive to perforation phasing than to the number of perforations in clusters. Alterations of the number of perforations per cluster within a stage enable achieving more even proppant distribution.
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Benjaboonyazit, Veerawit, Nithipoom Durongwattana, Sompop Buapha, Kittipat Wejwittayaklung, and Phattarakorn Rangsriwong. "Drilling and Well Digitalization, A Journey of Transformation." In IADC/SPE Asia Pacific Drilling Technology Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/209872-ms.
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Abstract The Company's digital transformation project was started in 2018 to overcome the challenge from digital disruption, energy transition and hydrocarbon reserves declination. Drilling and well engineering cluster is a key player in operating cost optimization which requires digestion and analysis of tons of data generated through daily operational reports. Thus, several digitalization projects have been initiated to optimize drilling and well process to be better, faster, and safer. In this paper, we intend to share a successful journey of digitalization under drilling and well cluster. The transformation journey started with identifying engineer's pain points in each process, among which the most common were redundant processes, manual data inputs/calculations, and time spent on collecting and analyzing unstructured data sources. Moreover, diversified practices on engineering programs and data analysis adversely affect well design standardization and optimizations. To counter those pain points, digital transformation projects were ideated by using digital solutions and technology which are grouped in 5 focus areas: centralized data platform, business intelligence, robotic process automation, digital assistant, and data analytics from fundamental to advance level respectively. Besides out-of-the-box solutions, many internally developed systems have been utilized throughout the journey which helps engineers to build their digital capability and awareness. There are over twenty (20) drilling and well digital projects implemented since the transformation project has been started. And as a result, engineers’ workload has been reduced significantly using digital solutions such as data extraction, visualization, and in-depth analysis. For example, the first successful project under robotic process automation utilizes text analytic and Artificial Intelligence (AI) techniques to analyze well conditions and integrity status from unstructured data and to generate reports within a limited timeframe. Another successful case is well design automated workflow which saved around 40% planning cycle time and provides a better design quality which will lead to a lower well cost. Total cost saving of over 40 mmusd has been recorded so far under the digital transformation project. Furthermore, there is an outlook for additional cost-saving through future new projects, integration, and scaling up plans across the company's international assets. The results and outcomes are very promising to this point. We believe that these initiatives will help the company to improve productivity, benefits, agility, and move beyond business disruptions. Combination of drilling and well expertise with digital transformation solutions will significantly improve well design process, quality and operational efficiency which make industry stay competitive and resilient in the future.
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Zeinabady, Danial, Behnam Zanganeh, Sadeq Shahamat, and Christopher R. Clarkson. "Application of DFIT-FBA Tests Performed at Multiple Points in a Horizontal Well for Advanced Treatment Stage Design and Reservoir Characterization." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204200-ms.
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Abstract The DFIT flowback analysis (DFIT-FBA) method, recently developed by the authors, is a new approach for obtaining minimum in-situ stress, reservoir pressure, and well productivity index estimates in a fraction of the time required by conventional DFITs. The goal of this study is to demonstrate the application of DFIT-FBA to hydraulic fracturing design and reservoir characterization by performing tests at multiple points along a horizontal well completed in an unconventional reservoir. Furthermore, new corrections are introduced to the DFIT-FBA method to account for perforation friction, tortuosity, and wellbore unloading during the flowback stage of the test. The time and cost efficiency associated with the DFIT-FBA method provides an opportunity to conduct multiple field tests without delaying the completion program. Several trials of the new method were performed for this study. These trials demonstrate application of the DFIT-FBA for testing multiple points along the lateral of a horizontal well (toe stage and additional clusters). The operational procedure for each DFIT-FBA test consists of two steps: 1) injection to initiate and propagate a mini hydraulic fracture and 2) flowback of the injected fluid on surface using a variable choke setting on the wellhead. Rate transient analysis methods are then applied to the flowback data to identify flow regimes and estimate closure and reservoir pressure. Flowing material balance analysis is used to estimate the well productivity index for studied reservoir intervals. Minimum in-situ stress, pore pressure and well productivity index estimates were successfully obtained for all the field trials and validated by comparison against a conventional DFIT. The new corrections for friction and wellbore unloading improved the accuracy of the closure and reservoir pressures by 4%. Furthermore, the results of flowing material balance analysis show that wellbore unloading might cause significant over-estimation of the well productivity index. Considerable variation in well productivity index was observed from the toe stage to the heel stage (along the lateral) for the studied well. This variation has significant implications for hydraulic fracture design optimization, particularly treatment pressures and volumes.
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Liu, Yaowen, Wei Pang, Jincai Shen, and Ying Mi. "Comprehensive Analysis of Production Loggings in Fuling Shale Gas Play in China." In SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204762-ms.
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Abstract Fuling shale gas field is one of the most successful shale gas play in China. Production logging is one of the vital technologies to evaluate the shale gas contribution in different stages and different clusters. Production logging has been conducted in over 40 wells and most of the operations are successful and good results have been observed. Some previous studies have unveiled one or several wells production logging results in Fuling shale gas play. But production logging results show huge difference between different wells. In order to get better understanding of the results, a comprehensive overview is carried out. The effect of lithology layers, TOC (total organic content), porosity, brittle mineral content, well trajectory is analyzed. Results show that the production logging result is consistent with the geology understanding, and fractures in the favorable layers make more gas contribution. Rate contribution shows positive correlation with TOC, the higher the TOC, the greater the rate contribution per stage. For wells with higher TOC, the rate contribution difference per stage is relatively smaller, but for wells with lower TOC, it shows huge rate contribution variation, fracture stages with TOC lower than 2% contribute very little, and there exist one or several dominant fractures which contributes most gas rate. Porosity and brittle minerals also show positive effect on rate contribution. The gas rate contribution per fracture stage increases with the increase of porosity and brittle minerals. The gas contribution of the front half lateral and that of latter half lateral are relatively close for the "upward" or horizontal wells. However, for the "downward" wells, the latter half lateral contribute much more gas than the front half lateral. It is believed that the liquid loading in the toe parts reduced the gas contribution in the front half lateral. The overview research is important to get a compressive understanding of production logging and different fractures’ contribution in shale gas production. It is also useful to guide the design of horizontal laterals and fractures scenarios design.
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Kolle, Jack, Alan Mueller, Steve Baumgartner, and David Cuthill. "Modeling Proppant Transport in Casing and Perforations Based on Proppant Transport Surface Tests." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/209178-ms.
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Abstract The results of a series of proppant transport surface tests (PTSTs) were used in conjunction with Eulerian multiphase-computational fluid dynamics (EMP-CFD) modeling to develop an engineering model of proppant distribution. The PTSTs were carried out to evaluate proppant placement through perforated casing. In these tests, sand slurry was pumped at realistically high flow rates through perforated casing and the distribution of sand and slurry from each perforation cluster was observed. The tests show that gravitational settling in horizontal casing, proppant slip past perforations and the visco-elastic properties of slickwater fluids strongly affect the distribution of proppant from the heel to the toe of the completion. The EMP-CFD modeling was used to estimate the gravitational settling of sand in fully-developed turbulent slurry flow in horizontal casing as a function of casing velocity. A survey of 36 calculations was carried out to generate tables of sand concentration in a cross section through the casing as a function of flow rate and particle size. A single-phase CFD analysis showed how sand exiting each perforation is taken from a limited ingestion area which is proportional to the ratio of flow through the perforation to total flow in the casing. A detailed EMP-CFD analysis of flow through single perforations showed how sand slips past the perforation. The results of 28 EMP-CFD calculations provided slip factors as a function of particle size, casing flow velocity, and perforation flow velocity in straight and angled perforations. The EMP-CFD settling tables and a parameterization of the slip factors were integrated into an engineering model. The model predicts the distribution of slurry and sand through each perforation based on the proppant size, perforation phase angle, and pump rate. The engineering model was used to predict the sand distributions observed in the PTSTs. The PTSTs were conducted with a range of sand sizes and with low-viscosity friction reducing polymer (FR) additives, while the EMP-CFD analysis assumed water. A weight factor is introduced in the settling model to account for the increased dispersion of sand in water with low viscosity FR and to match the observed sand distributions in the PTSTs. The observed slip of 100 Mesh and 40/70 Mesh sand is consistent with the EMP-CFD calculations in water. The model reflects the PTST observations that fine sand is distributed relatively uniformly throughout the length of a perforated completion while coarser sand tends to slip past the heel perforations and concentrate on the bottom towards the toe of the completion.
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Ma, Ming, Owen Hughes, and Tobin McNatt. "Ultimate Limit State Based Ship Structural Design Using Multi-Objective Discrete Particle Swarm Optimization." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41456.
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Multi-objective optimization problems consist of several objectives that must be handled simultaneously. These objectives usually conflict with each other, and optimizing a particular solution with respect to a single objective can result in unacceptable results with respect to the other objectives. A reasonable solution to a multi-objective problem is to investigate a set of solutions, each of which satisfies the objectives at an acceptable level without being dominated by any other solution. Genetic or evolution algorithms have been demonstrated to be particularly effective to determine excellent solutions to these problems. Among many algorithms, the particle swarm optimization (PSO) has been found to be faster with less computational overhead. In this paper a multi-objective discrete particle swarm optimization is formulated and used to optimize a large and complex thin-wall structure on the basis of weight, safety and cost. The structure weight and cost are calculated using realistic finite element models. The design process has two stages: (1) the actual stresses are obtained by finite element analysis of the full ship, (2) for a midship segment of the ship (referred to as a “control cluster”) the structural safety is evaluated using the ALPS/ULSAP set of ultimate limit state criteria, and then the segment is optimized using any suitable optimization method (in this paper, the PSO method). Both stages involve iteration, but the process is arranged so as to keep the number of full ship finite element analyses to a minimum. The complete design process is illustrated for a 200,000 ton oil tanker. The numerical results show that the PSO method is very useful to perform ultimate strength based ship structural optimization with multi-objectives, namely minimization of the structural weight and cost and maximization of structural safety. The example also demonstrates that the proper definition of boundary conditions and design load cases is of paramount importance for design optimization.
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Zhao, Hefei, and Selina Wang. "Isolation and purification phenolic compounds in California olive pomace by pilot-scale C18 gel chromatography." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/hkjz6249.
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According to the Food and Agriculture Organization, the United States (mainly in California) produced 151,950 tons of olives in 2019, which resulted in a large amount of pomace waste. While many researchers focused on crude extraction and macroporous resin purification from European olive pomace on an analytical scale, few studies have been conducted to isolate fractions of US olive pomase (OP) by pilot-scale C18 chromatography. Hexane defatted Arbequina California OP was extracted by water, and the extract was loaded to a pilot-scale chromatography column with 262.5 mL C18 gel, and the elute syrup (ES) was collected. Desorptions were applied by 1 L of acidified water (AW), 35% methanol (35M) and 70% methanol (70M), respectively. The fractions were concentrated then freeze-dried. Total phenol contents (TPC) were measured by Folin-Ciocalteu assay. Individual phenols were determined by HPLC-DAD. Results showed that the TPC of the fractions of ES, AW, 35M and 70M were 2.88, 29.39, 170.56 and 235.96 mg gallic acid equivalents/g, respectively. Heatmap cluster analysis showed that ES and AW fractions had similar phenol profiles with hydroxytyrosol and tyrosol-glucoside; and 35M had hydroxytyrosol-glucoside, hydroxytyrosol, tyrosol-glucoside, 4-hydroxyphenylacetic acid (4-HPA), verbascoside and oleuropein; 70M contained hydroxytyrosol, tyrosol-glucoside, tyrosol, but generally had more nonpolar compounds such as verbascoside, rutin and oleuropein. Very interestingly, the 3,4-DHPEA-EDA in water extract at 31.43 min disappeared in 35M and 70M fractions, meanwhile a new peak at 29.25 min showed up which could be a new compound derived from 3,4-DHPEA-EDA possibly because of the acidified process. This study could be the first-ever report of phenol profile of pilot-scale C18 fractions of the US OP. This new data on the chemical compositions of the OP C18 fractions provides practical knowledge for the valorization and industrial food applications of the US olive wastes.
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Nicholson, A. Kirby, Robert C. Bachman, R. Yvonne Scherz, and Robert V. Hawkes. "Low-Cost Measurement of Hydraulic Fracture Dimensions Using Pressure Data in Treatment and Observation Wells – A Workflow for Every Well." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204183-ms.
Full textAbstract:
Abstract Pressure and stage volume are the least expensive and most readily available data for diagnostic analysis of hydraulic fracturing operations. Case history data from the Midland Basin is used to demonstrate how high-quality, time-synchronized pressure measurements at a treatment and an offsetting shut-in producing well can provide the necessary input to calculate fracture geometries at both wells and estimate perforation cluster efficiency at the treatment well. No special wellbore monitoring equipment is required. In summary, the methods outlined in this paper quantifies fracture geometries as compared to the more general observations of Daneshy (2020) and Haustveit et al. (2020). Pressures collected in Diagnostic Fracture Injection Tests (DFITs), select toe-stage full-scale fracture treatments, and offset observation wells are used to demonstrate a simple workflow. The pressure data combined with Volume to First Response (Vfr) at the observation well is used to create a geometry model of fracture length, width, and height estimates at the treatment well as illustrated in Figure 1. The producing fracture length of the observation well is also determined. Pressure Transient Analysis (PTA) techniques, a Perkins-Kern-Nordgren (PKN) fracture propagation model and offset well Fracture Driven Interaction (FDI) pressures are used to quantify hydraulic fracture dimensions. The PTA-derived Farfield Fracture Extension Pressure, FFEP, concept was introduced in Nicholson et al. (2019) and is summarized in Appendix B of this paper. FFEP replaces Instantaneous Shut-In Pressure, ISIP, for use in net pressure calculations. FFEP is determined and utilized in both DFITs and full-scale fracture inter-stage fall-off data. The use of the Primary Pressure Derivative (PPD) to accurately identify FFEP simplifies and speeds up the analysis, allowing for real time treatment decisions. This new technique is called Rapid-PTA. Additionally, the plotted shape and gradient of the observation-well pressure response can identify whether FDI's are hydraulic or poroelastic before a fracture stage is completed and may be used to change stage volume on the fly. Figure 1Fracture Geometry Model with FDI Pressure Matching Case studies are presented showing the full workflow required to generate the fracture geometry model. The component inputs for the model are presented including a toe-stage DFIT, inter-stage pressure fall-off, and the FDI pressure build-up. We discuss how to optimize these hydraulic fractures in hindsight (look-back) and what might have been done in real time during the completion operations given this workflow and field-ready advanced data-handling capability. Hydraulic fracturing operations can be optimized in real time using new Rapid-PTA techniques for high quality pressure data collected on treating and observation wells. This process opens the door for more advanced geometry modeling and for rapid design changes to save costs and improve well productivity and ultimate recovery.
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Audivet Durán, Cinthia, and Marco E. Sanjuán. "On-Line Early Fault Detection of a Centrifugal Chiller Based on Data Driven Approach." In ASME 2016 10th International Conference on Energy Sustainability collocated with the ASME 2016 Power Conference and the ASME 2016 14th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/es2016-59291.
Full textAbstract:
A district cooling system (DCS) is a system that distributes thermal energy through chilled water from a central source to residential, commercial, or industrial consumers, designated to air conditioning purposes. It is one of the most important part of a heating, ventilation, air conditioning and refrigeration systems (HVAC), because a DCS is composed of: Cooling towers, central chiller plant, water distribution systems and clusters of consumer buildings. This research is focused on the central chiller plant, due to it accounts for a substantial portion of the total energy consume of DCS and HVAC systems. The performance of central chiller plant is often affected by multiple faults which could be caused during installation or developed in routine operation. These non-optimal conditions and faults may cause 20–30% waste of energy consumption of HVAC&R systems. Automated fault detection and diagnosis (AFDD) tools have potential to detect an incipient fault and help to reduce undesirable conditions and energy consumption, and optimize the facility maintenance. We propose an online data driven fault detection strategy for district cooling system. The main objective is to develop an automated fault detection tool based on historical process data, which can be applied in transient operation. The proposed hybrid strategy is based on unsupervised and supervised learning techniques, and multivariate statistic techniques. Its aim is to identify the operating states of the chiller and evaluate the fault occurrence depending of its current operating state. This strategy uses the K-means clustering method, Naive Bayes classifier and Principal Component Analysis (PCA). The developed strategy was evaluated using the performance data of a 90-ton water-cooled centrifugal chiller (ASHRAE RP-1043) and also evaluated using a dynamic model of a chiller (Simscape™.) under similar conditions. The results show the advantages of novel early fault detection technique compared to Conventional PCA method in terms of sensitivity to faults occurrence and reduction of missed detection rate.