Academic literature on the topic 'Key process parameters'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Key process parameters.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Key process parameters"
1
Bernacchi, Sébastien, Michaela Weissgram, Walter Wukovits, and Christoph Herwig. "Process efficiency simulation for key process parameters in biological methanogenesis." AIMS Bioengineering 1, no. 1 (2014): 53–71. http://dx.doi.org/10.3934/bioeng.2014.1.53.
Full text
2
Wett, B., S. Murthy, I. Takács, M. Hell, G. Bowden, A. Deur, and M. O'Shaughnessy. "Key Parameters for Control of DEMON Deammonification Process." Water Practice 1, no. 5 (November 12, 2007): 1–11. http://dx.doi.org/10.2175/193317707x257017.
Full text
3
Wett, B., S. Murthy, I. Tak´cs, M. Hell, G. Bowden, A. Deur, and M. O'Shaughnessy. "KEY PARAMETERS FOR CONTROL OF DEMON DEAMMONIFICATION PROCESS." Proceedings of the Water Environment Federation 2007, no. 2 (January 1, 2007): 424–36. http://dx.doi.org/10.2175/193864707787977181.
Full text
4
Maiti, Syamal, Dipayan Das, and Kushal Sen. "Electrochemical Polymerization of Pyrrole: Key Process Control Parameters." Journal of The Electrochemical Society 159, no. 9 (2012): E154—E158. http://dx.doi.org/10.1149/2.050209jes.
Full text
5
Krystynik, Pavel, and Duarte Novaes Tito. "Key process parameters affecting performance of electro-coagulation." Chemical Engineering and Processing: Process Intensification 117 (July 2017): 106–12. http://dx.doi.org/10.1016/j.cep.2017.03.022.
Full text
6
Mohammed, Seydaliyev Ilham. "Key Parameters Survey of the Magnetic System of the Electromagnetic Thickness Converter in the Process of Winding." Journal of Advanced Research in Dynamical and Control Systems 12, no. 01-Special Issue (February 13, 2020): 944–52. http://dx.doi.org/10.5373/jardcs/v12sp1/20201145.
Full text
7
Cotton, D., A. Maillard, and J. Kaufmann. "Improved coining force calculations through incorporation of key process parameters." IOP Conference Series: Materials Science and Engineering 967 (November 19, 2020): 012003. http://dx.doi.org/10.1088/1757-899x/967/1/012003.
Full text
8
Hoffman, R. D., S. E. Woosley, and Y. Z. Qian. "Model independent r-process nucleosynthesis — Constraints on the key parameters." Nuclear Physics A 621, no. 1-2 (August 1997): 397–400. http://dx.doi.org/10.1016/s0375-9474(97)00278-9.
Full text
9
Meng, Wen, and Guo-qun Zhao. "Effects of Key Simulation Parameters on Conical Ring Rolling Process." Procedia Engineering 81 (2014): 286–91. http://dx.doi.org/10.1016/j.proeng.2014.09.165.
Full text
10
Pan, Ri, Bo Zhong, Zhenzhong Wang, Shuting Ji, Dongju Chen, and Jinwei Fan. "Influencing mechanism of the key parameters during bonnet polishing process." International Journal of Advanced Manufacturing Technology 94, no. 1-4 (August 15, 2017): 643–53. http://dx.doi.org/10.1007/s00170-017-0870-4.
Full textDissertations / Theses on the topic "Key process parameters"
1
D'Costa, Aspen. "Characterization of key process parameters in injection blow molding for improving quality /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456293971&sid=9&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Full text
2
Fenollosa, Artés Felip. "Contribució a l'estudi de la impressió 3D per a la fabricació de models per facilitar l'assaig d'operacions quirúrgiques de tumors." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667421.
Full textAbstract:
La present tesi doctoral s’ha centrat en el repte d’aconseguir, mitjançant Fabricació Additiva (FA), models per a assaig quirúrgic, sota la premissa que els equips per fer-los haurien de ser accessibles a l’àmbit hospitalari. L’objectiu és facilitar l’extensió de l’ús dels prototips com a eina de preparació d’operacions quirúrgiques, transformant la pràctica mèdica actual de la mateixa manera que en el seu moment ho van fer tecnologies com les que van facilitar l’ús de radiografies. El motiu d’utilitzar FA, en lloc de tecnologies més tradicionals, és la seva capacitat de materialitzar de forma directa les dades digitals obtingudes de l’anatomia del pacient mitjançant sistemes d’escanejat tridimensional, fent possible l’obtenció de models personalitzats. Els resultats es centren en la generació de nou coneixement sobre com aconseguir equipaments d’impressió 3D multimaterials accessibles que permetin l’obtenció de models mimètics respecte als teixits vius. Per facilitar aquesta buscada extensió de la tecnologia, s’ha focalitzat en les tecnologies de codi obert com la Fabricació per Filament Fos (FFF) i similars basades en líquids catalitzables. La recerca s’alinea dins l’activitat de desenvolupament de la FA al CIM UPC, i en aquest àmbit concret amb la col·laboració amb l’Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloc de la tesi inclou la descripció de l’estat de l’art, detallant les tecnologies existents i la seva aplicació a l’entorn mèdic. S’han establert per primer cop unes bases de caracterització dels teixits vius -sobretot tous- per donar suport a la selecció de materials que els puguin mimetitzar en un procés de FA, a efectes de millorar l’experiència d’assaig dels cirurgians. El caràcter rígid dels materials majoritàriament usats en impressió 3D els fa poc útils per simular tumors i altres referències anatòmiques. De forma successiva, es tracten paràmetres com la densitat, la viscoelasticitat, la caracterització dels materials tous a la indústria, l’estudi del mòdul elàstic de teixits tous i vasos, la duresa d’aquests, i requeriments com l’esterilització dels models. El segon bloc comença explorant la impressió 3D mitjançant FFF. Es classifiquen les variants del procés des del punt de vista de la multimaterialitat, essencial per fer models d’assaig quirúrgic, diferenciant entre solucions multibroquet i de barreja al capçal. S’ha inclòs l’estudi de materials (filaments i líquids) que serien més útils per mimetitzar teixits tous. Es constata com en els líquids, en comparació amb els filaments, la complexitat del treball en processos de FA és més elevada, i es determinen formes d’imprimir materials molt tous. Per acabar, s’exposen sis casos reals de col·laboració amb l’HJSD, una selecció d’aquells en els que el doctorand ha intervingut en els darrers anys. L’origen es troba en la dificultat de l’abordatge d’operacions de resecció de tumors infantils com el neuroblastoma, i a la iniciativa del Dr. Lucas Krauel. Finalment, el Bloc 3 té per objecte explorar nombrosos conceptes (fins a 8), activitat completada al llarg dels darrers cinc anys amb el suport dels mitjans del CIM UPC i de l’activitat associada a treballs finals d’estudis d’estudiants de la UPC, arribant-se a materialitzar equipaments experimentals per validar-los. La recerca ampla i sistemàtica al respecte fa que s’estigui més a prop de disposar d’una solució d’impressió 3D multimaterial de sobretaula. Es determina que la millor via de progrés és la de disposar d’una pluralitat de capçals independents a fi de capacitar la impressora 3D per integrar diversos conceptes estudiats, materialitzant-se una possible solució. Cloent la tesi, es planteja com seria un equipament d’impressió 3D per a models d’assaig quirúrgic, a fi de servir de base per a futurs desenvolupaments.La presente tesis doctoral se ha centrado en el reto de conseguir, mediante Fabricación Aditiva (FA), modelos para ensayo quirúrgico, bajo la premisa que los equipos para obtenerlos tendrían que ser accesibles al ámbito hospitalario. El objetivo es facilitar la extensión del uso de modelos como herramienta de preparación de operaciones quirúrgicas, transformando la práctica médica actual de la misma manera que, en su momento, lo hicieron tecnologías como las que facilitaron el uso de radiografías. El motivo de utilizar FA, en lugar de tecnologías más tradicionales, es su capacidad de materializar de forma directa los datos digitales obtenidos de la anatomía del paciente mediante sistemas de escaneado tridimensional, haciendo posible la obtención de modelos personalizados. Los resultados se centran en la generación de nuevo conocimiento para conseguir equipamientos de impresión 3D multimateriales accesibles que permitan la obtención de modelos miméticos respecto a los tejidos vivos. Para facilitar la buscada extensión de la tecnología, se ha focalizado en las tecnologías de código abierto como la Fabricación por Hilo Fundido (FFF) y similares basadas en líquidos catalizables. Esta investigación se alinea dentro de la actividad de desarrollo de la FA en el CIM UPC, y en este ámbito concreto con la colaboración con el Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloque de la tesis incluye la descripción del estado del arte, detallando las tecnologías existentes y su aplicación al entorno médico. Se han establecido por primera vez unas bases de caracterización de los tejidos vivos – principalmente blandos – para dar apoyo a la selección de materiales que los puedan mimetizar en un proceso de FA, a efectos de mejorar la experiencia de ensayo de los cirujanos. El carácter rígido de los materiales mayoritariamente usados en impresión 3D los hace poco útiles para simular tumores y otras referencias anatómicas. De forma sucesiva, se tratan parámetros como la densidad, la viscoelasticidad, la caracterización de materiales blandos en la industria, el estudio del módulo elástico de tejidos blandos y vasos, la dureza de los mismos, y requerimientos como la esterilización de los modelos. El segundo bloque empieza explorando la impresión 3D mediante FFF. Se clasifican las variantes del proceso desde el punto de vista de la multimaterialidad, esencial para hacer modelos de ensayo quirúrgico, diferenciando entre soluciones multiboquilla y de mezcla en el cabezal. Se ha incluido el estudio de materiales (filamentos y líquidos) que serían más útiles para mimetizar tejidos blandos. Se constata como en los líquidos, en comparación con los filamentos, la complejidad del trabajo en procesos de FA es más elevada, y se determinan formas de imprimir materiales muy blandos. Para acabar, se exponen seis casos reales de colaboración con el HJSD, una selección de aquellos en los que el doctorando ha intervenido en los últimos años. El origen se encuentra en la dificultad del abordaje de operaciones de resección de tumores infantiles como el neuroblastoma, y en la iniciativa del Dr. Lucas Krauel. Finalmente, el Bloque 3 desarrolla numerosos conceptos (hasta 8), actividad completada a lo largo de los últimos cinco años con el apoyo de los medios del CIM UPC y de la actividad asociada a trabajos finales de estudios de estudiantes de la UPC, llegándose a materializar equipamientos experimentales para validarlos. La investigación amplia y sistemática al respecto hace que se esté más cerca de disponer de una solución de impresión 3D multimaterial de sobremesa. Se determina que la mejor vía de progreso es la de disponer de una pluralidad de cabezales independientes, a fin de capacitar la impresora 3D para integrar diversos conceptos estudiados, materializándose una posible solución. Para cerrar la tesis, se plantea cómo sería un equipamiento de impresión 3D para modelos de ensayo quirúrgico, a fin de servir de base para futuros desarrollos.
3
Chung, Ming-ju, and 鍾明儒. "Study on key process parameters for laser-gelling rapid prototyping." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/71255337937398717291.
Full textAbstract:
碩士龍華科技大學
工程技術研究所
100
Laser-gelling stacking techniques have been used in rapid prototyping for many years and its products are popular for cases with lower quality requirement. But, its products cannot be accepted for cases with higher quality requirement now, so some key process parameters of the techniques must be set appropriately to increase the quality of products created by the techniques. Therefore, this paper studies the control of scanning line widths, the homogenity for stacking layers of a product, the warpping of a product, the aperture distortion of remained holes, the repeatability of products, and the acceleration areas of scanning to find the appropriate setting values for some key process parameters. In all experiments, cases without appropriate setting and cases with appropriate setting are both performed. The created products show cases with appropriate setting are always better. The setting of key parameters can be done with setups using modified rapid prototyping and appropriate setting of key parameters may be a good way to make laser-gelling stacking techniques belong to precise machining.
4
Vatta, Laura Lisa. "Manufacture of ferrofluid : basic aspects and the influence of key parameters on the process." Diss., 2003. http://hdl.handle.net/2263/24792.
Full text
5
Yang, Chih-Cheng, and 楊志誠. "Key Parameters Optimization Applying Six Sigma Methodology and Artificial Neural Network to a Multi-Range Curvature Optical Surface Grinding Process." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/56484523864412368666.
Full textAbstract:
碩士國立中央大學
光電科學研究所碩士在職專班
93
Surfacing technology for optical components has been well established for almost 250 years. The industry has continued to grow vigorously mostly because of new applications. Throughout the long development history, many different designs and materials were applied; however, the process and challenges of today remain similar to those experienced from the very beginning. Processed surface quality is one of the key factors in achieving good optical performance. Although the modern machines are now equipped with better capabilities, optimization of operation conditions by skilled technicians remains a requirement. Especially, the best control parameters require practices that include trade-offs during prototyping and production startup. Moreover, time-consuming trial and error methods based on experience remain a general practice. All optical components follow the same three-phase surfacing process in general including: 1st - Generating, 2nd - Fine grinding, (or smoothing), 3rd - Polishing. The Fine grinding phase was identified as the most critical process for production efficiency, quality yield, and component performance. Thus, this experimental design focuses on the fine grinding process. The experiment design in this paper applied the general use ophthalmic spherical power range as study case. The lenses design including meniscus concave lens for myopia correction and periscopic convex lens for hyperopia or presbyopia correction. There are total 57 sets curvature designs with 0.25D step international ophthalmic standard spherical power range form S-7.00D to S+7.00D. This paper shows how process optimization can be achieved in two steps, the first step using Six Sigma methodology gauges the surfacing process control in order to confirm the five general specified factors that are critical to the surfacing operation. A second effective method coupling the Taguchi experimental design and the most important improvement tools of Six Sigma methodology was then applied. The design plan is based on the use of orthogonal arrays introduced by Taguchi. Through the application of Taguchi’s signal-to-noise (S/N) ratio, we demonstrate that the best parameters design plan from an experimental design can be determined. This has several implications: (1) It reduces the implementation time, (2) it can identify a fractional design that contains the best design plan and that design plan could be studied for full experimentation, (3) within a subset of a fractional design plan, the best design point can be found, and (4) the cost of experimentation is significantly reduced since a minimal number of runs is required to identify the best design point. Finally, this important result helps experimenters to select a fractional design plan that contains the “best design point.” The experiment condition for example, it takes minimum﹙53 x 53 =15,625﹚15,625 experiment trials if using the traditional trial and error methods in order to find the optimal parameters. The fact, the results prove the optimal parameters can be found and confirmed with only (18 x 3 =54) 54 trials according to the design in this paper. The result shows it takes only 0.34% time if the same effect use the traditional trial and error non-specific methods. The traditional control parameters require practices which include trade-offs by skilled senior engineers who are required at this moment to make experiential judgments. In this article, optimized parameters are obtained by applying the mathematical exercise of Non-linear “Artificial Neural Network” to eliminate the subjective judgments. It replaces the errors caused from the experiential judgments made by the expert senior engineers. In terms of the production equipment control and adjustment ability of the newly recruited technician, their capability for exact and reasonable recognition of the production parameters set up is substantially improved. Moreover, the optimal parameters can be applied as the default factory setting in order to be utilized as the reference parameters for general production purposes.
Books on the topic "Key process parameters"
1
Apostolidi, Eftychia, Stephanos Dritsos, Christos Giarlelis, José Jara, Fatih Sutcu, Toru Takeuchi, and Joe White. Seismic Isolation and Response Control. Edited by Andreas Lampropoulos. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2021. http://dx.doi.org/10.2749/sed019.
Full textAbstract:
<p>The seismic resilience of new and existing structures is a key priority for the protection of human lives and the reduction of economic losses in earthquake prone areas. The modern seismic codes have focused on the upgrade of the structural performance of the new and existing structures. However, in many cases it is preferrable to mitigate the effects of the earthquakes by reducing the induced loads in the structures using seismic isolation and response control devices. The limited expertise in the selection and design of the appropriate system for new and existing structures is the main challenge for an extensive use of seismic isolation and response control systems in practice.</p> <p>This document aims to provide a practical guide by presenting a collection of the most commonly used seismic isolation and response control systems and a critical evaluation of the main characteristics of these systems. Comparisons of the key parameters of the design processes for new buildings with seismic isolation are presented, while the application of seismic isolation systems and response control systems for the retrofitting of existing structures is also examined, followed by various case studies from Greece, Japan, Mexico, New Zealand, and Turkey.</p>
2
Department of Defense. F-15A Versus F/a-22 Fighter Aircraft Initial Operational Capability: A Case for Transformation - Test and Evaluation Process, Critical Issues, Key Performance Parameters, Langley Air Force Base. Independently Published, 2017.
Find full text
3
Jacobson, David M., and Giles Humpston. Principles of Brazing. ASM International, 2005. http://dx.doi.org/10.31399/asm.tb.pb.9781627083515.
Full textAbstract:
Principles of Brazing serves as a problem-solving guide for anyone who works with brazing processes or designs component joints. It covers key brazing parameters such as surface energy and tension, wetting and contact angle, and filler spreading characteristics; design considerations including mechanical integrity and electrical and thermal conductivity; and practical concerns such as workholding, cleaning procedures, and process control. It discusses the metallurgy of brazing alloy systems; the effect of impurities, joining atmospheres, and chemical fluxes; and the role of materials in defining process constraints. It also provides information on diffusion brazing, direct brazing processes for nonmetals, and brazes for jewelry. For information on the print version, ISBN 978-0-87170-812-0, follow this link.
4
Humpston, Giles, and David M. Jacobson. Principles of Soldering. ASM International, 2004. http://dx.doi.org/10.31399/asm.tb.ps.9781627083522.
Full textAbstract:
Principles of Soldering serves as a problem-solving guide for engineers who work with soldering processes and soldered components and assemblies. It begins with a review of key process parameters, including surface energy and tension, wetting and contact angle, fluid flow, filler spreading characteristics, dissolution of parent materials, and intermetallic growth. It then examines the factors that influence the functional integrity of soldered joints and the practicality of the process employed. It discusses the metallurgy of solder alloy systems, the effect of metallic impurities, and the use of phase diagrams to better understand and control the soldering process. It explains how joining atmospheres influence chemical reactions and how fluxes help remove surface oxides and other films. It describes the benefits of fluxless soldering and the role of materials in defining process constraints. It also covers lead-free solders, bump bonding, amalgams, and diffusion soldering as well as mechanical property testing, joint characterization and modeling techniques, and solderability standards. For information on the print version, ISBN 978-0-87170-792-5, follow this link.
5
Peach, Ken. Managing Projects. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198796077.003.0012.
Full textAbstract:
This chapter reviews and provides examples of elements and techniques of project management. In the good old days, when conception to completion was a few months, the process of project management was relatively informal. However, with the increasing complexity and cost of projects, many routinely costing millions and some costing billions, the process has become more formalized. This chapter discusses the roles of the client, the sponsor, the leader, the manager and the team member. In addition, the three key parameters of project management, quality, cost and schedule, are defined and discussed. Finally, various project management methodologies and tools, such as work breakdown structures, Gantt charts and milestones, are presented.
6
Lowe, Ben, ed. Political Thought and the Origins of the American Presidency. University Press of Florida, 2021. http://dx.doi.org/10.5744/florida/9780813066813.001.0001.
Full textAbstract:
This volume examines the political ideas behind the construction of the presidency in the U.S. Constitution, as well as how these ideas were implemented by the nation’s early presidents. The framers of the Constitution disagreed about the scope of the new executive role they were creating, and this volume reveals the ways the duties and power of the office developed contrary to many expectations. Here, leading scholars of the early republic examine principles from European thought and culture that were key to establishing the conceptual language and institutional parameters for the American executive office. Unpacking the debates at the 1787 Constitutional Convention, these essays describe how the Constitution left room for the first presidents to set patterns of behavior and establish a range of duties to make the office functional within a governmental system of checks and balances. Contributors explore how these presidents understood their positions and fleshed out their full responsibilities according to the everyday operations required to succeed. As disputes continue to surround the limits of executive power today, this volume helps identify and explain the circumstances in which limits can be imposed on presidents who seem to dangerously exceed the constitutional parameters of their office. Political Thought and the Origins of the American Presidency demonstrates that this distinctive, time-tested role developed from a fraught, historically contingent, and contested process.
7
Braidotti, Rosi, and Patricia Pisters, eds. Revisiting Normativity with Deleuze. Bloomsbury Publishing Plc, 2012. http://dx.doi.org/10.5040/9781350275911.
Full textAbstract:
This volume assembles some of the most distinguished scholars in the field of Deleuze studies in order to provide both an accessible introduction to key concepts in Deleuze's thought and to test them in view of the issue of normativity. This includes not only the law, but also the question of norms and values in the broader ethical, political and methodological sense. The volume argues that Deleuze's philosophy rejects the unitary vision of the subject as a self-regulating rationalist entity and replaces it with a process-oriented relational vision of the subject. But what can we do exactly with this alternative nomadic vision? What modes of normativity are available outside the parameters of liberal, self-reflexive individualism on the one hand and the communitarian model on the other? This interdisciplinary volume explores these issues in three directions that mirror Deleuze and Guattari's defense of the parallelism between philosophy, science, and the arts. The volume therefore covers socio-political and legal theory; the epistemological critique of scientific discourse and the cultural, artistic and aesthetic interventions emerging from Deleuze's philosophy.
8
Sobczyk, Eugeniusz Jacek. Uciążliwość eksploatacji złóż węgla kamiennego wynikająca z warunków geologicznych i górniczych. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN, 2022. http://dx.doi.org/10.33223/onermin/0222.
Full textAbstract:
Hard coal mining is characterised by features that pose numerous challenges to its current operations and cause strategic and operational problems in planning its development. The most important of these include the high capital intensity of mining investment projects and the dynamically changing environment in which the sector operates, while the long-term role of the sector is dependent on factors originating at both national and international level. At the same time, the conditions for coal mining are deteriorating, the resources more readily available in active mines are being exhausted, mining depths are increasing, temperature levels in pits are rising, transport routes for staff and materials are getting longer, effective working time is decreasing, natural hazards are increasing, and seams with an increasing content of waste rock are being mined. The mining industry is currently in a very difficult situation, both in technical (mining) and economic terms. It cannot be ignored, however, that the difficult financial situation of Polish mining companies is largely exacerbated by their high operating costs. The cost of obtaining coal and its price are two key elements that determine the level of efficiency of Polish mines. This situation could be improved by streamlining the planning processes. This would involve striving for production planning that is as predictable as possible and, on the other hand, economically efficient. In this respect, it is helpful to plan the production from operating longwalls with full awareness of the complexity of geological and mining conditions and the resulting economic consequences. The constraints on increasing the efficiency of the mining process are due to the technical potential of the mining process, organisational factors and, above all, geological and mining conditions. The main objective of the monograph is to identify relations between geological and mining parameters and the level of longwall mining costs, and their daily output. In view of the above, it was assumed that it was possible to present the relationship between the costs of longwall mining and the daily coal output from a longwall as a function of onerous geological and mining factors. The monograph presents two models of onerous geological and mining conditions, including natural hazards, deposit (seam) parameters, mining (technical) parameters and environmental factors. The models were used to calculate two onerousness indicators, Wue and WUt, which synthetically define the level of impact of onerous geological and mining conditions on the mining process in relation to: —— operating costs at longwall faces – indicator WUe, —— daily longwall mining output – indicator WUt. In the next research step, the analysis of direct relationships of selected geological and mining factors with longwall costs and the mining output level was conducted. For this purpose, two statistical models were built for the following dependent variables: unit operating cost (Model 1) and daily longwall mining output (Model 2). The models served two additional sub-objectives: interpretation of the influence of independent variables on dependent variables and point forecasting. The models were also used for forecasting purposes. Statistical models were built on the basis of historical production results of selected seven Polish mines. On the basis of variability of geological and mining conditions at 120 longwalls, the influence of individual parameters on longwall mining between 2010 and 2019 was determined. The identified relationships made it possible to formulate numerical forecast of unit production cost and daily longwall mining output in relation to the level of expected onerousness. The projection period was assumed to be 2020–2030. On this basis, an opinion was formulated on the forecast of the expected unit production costs and the output of the 259 longwalls planned to be mined at these mines. A procedure scheme was developed using the following methods: 1) Analytic Hierarchy Process (AHP) – mathematical multi-criteria decision-making method, 2) comparative multivariate analysis, 3) regression analysis, 4) Monte Carlo simulation. The utilitarian purpose of the monograph is to provide the research community with the concept of building models that can be used to solve real decision-making problems during longwall planning in hard coal mines. The layout of the monograph, consisting of an introduction, eight main sections and a conclusion, follows the objectives set out above. Section One presents the methodology used to assess the impact of onerous geological and mining conditions on the mining process. Multi-Criteria Decision Analysis (MCDA) is reviewed and basic definitions used in the following part of the paper are introduced. The section includes a description of AHP which was used in the presented analysis. Individual factors resulting from natural hazards, from the geological structure of the deposit (seam), from limitations caused by technical requirements, from the impact of mining on the environment, which affect the mining process, are described exhaustively in Section Two. Sections Three and Four present the construction of two hierarchical models of geological and mining conditions onerousness: the first in the context of extraction costs and the second in relation to daily longwall mining. The procedure for valuing the importance of their components by a group of experts (pairwise comparison of criteria and sub-criteria on the basis of Saaty’s 9-point comparison scale) is presented. The AHP method is very sensitive to even small changes in the value of the comparison matrix. In order to determine the stability of the valuation of both onerousness models, a sensitivity analysis was carried out, which is described in detail in Section Five. Section Six is devoted to the issue of constructing aggregate indices, WUe and WUt, which synthetically measure the impact of onerous geological and mining conditions on the mining process in individual longwalls and allow for a linear ordering of longwalls according to increasing levels of onerousness. Section Seven opens the research part of the work, which analyses the results of the developed models and indicators in individual mines. A detailed analysis is presented of the assessment of the impact of onerous mining conditions on mining costs in selected seams of the analysed mines, and in the case of the impact of onerous mining on daily longwall mining output, the variability of this process in individual fields (lots) of the mines is characterised. Section Eight presents the regression equations for the dependence of the costs and level of extraction on the aggregated onerousness indicators, WUe and WUt. The regression models f(KJC_N) and f(W) developed in this way are used to forecast the unit mining costs and daily output of the designed longwalls in the context of diversified geological and mining conditions. The use of regression models is of great practical importance. It makes it possible to approximate unit costs and daily output for newly designed longwall workings. The use of this knowledge may significantly improve the quality of planning processes and the effectiveness of the mining process.
9
Belekar, R. M., Renu Nayar, Pratibha Agrawal, and S. J. Dhoble, eds. Water Pollution Sources and Purification: Challenges and Scope. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/97898150506841220101.
Full textAbstract:
The book helps readers to understand the fundamentals of water purification processes. Chapters in the book cover industrial purification techniques, while also exploring the future scope and current challenges in this field. Key Features - Seven chapters arranged and structured in a clear, coherent manner for understanding the broad topics. - Covers basic water purification techniques for safe drinking water - Covers defluoridation techniques - Explains the parameters affecting photocatalytic degradation of substituted benzoic acids. - Includes a case study for seasonal variations in pond water - Covers the role of nanotechnology in wastewater treatment - Covers the impact of water mismanagement on the environment with suggestions for preventive measures for sustainable water utilization This reference informs advanced readers (sustainable development professionals, post-graduate and research scholars) interested in water treatment processes. It also serves as a resource for courses in environmental chemistry, waste management and sustainability.
10
Karatasakis, G., and G. D. Athanassopoulos. Cardiomyopathies. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0019.
Full textAbstract:
Echocardiography is a key diagnostic method in the management of patients with cardiomyopathies.The main echocardiographic findings of hypertrophic cardiomyopathy are asymmetric hypertrophy of the septum, increased echogenicity of the myocardium, systolic anterior motion, turbulent left ventricular (LV) outflow tract blood flow, intracavitary gradient of dynamic nature, mid-systolic closure of the aortic valve and mitral regurgitation. The degree of hypertrophy and the magnitude of the obstruction have prognostic meaning. Echocardiography plays a fundamental role not only in diagnostic process, but also in management of patients, prognostic stratification, and evaluation of therapeutic intervention effects.In idiopathic dilated cardiomyopathy, echocardiography reveals dilation and impaired contraction of the LV or both ventricles. The biplane Simpson’s method incorporates much of the shape of the LV in calculation of volume; currently, three-dimensional echocardiography accurately evaluates LV volumes. Deformation parameters might be used for detection of early ventricular involvement. Stress echocardiography using dobutamine or dipyridamole may contribute to risk stratification, evaluating contractile reserve and left anterior descending flow reserve. LV dyssynchrony assessment is challenging and in patients with biventricular pacing already applied, optimization of atrio-interventricular delays should be done. Specific characteristics of right ventricular dysplasia and isolated LV non-compaction can be recognized, resulting in an increasing frequency of their prevalence. Rare forms of cardiomyopathy related with neuromuscular disorders can be studied at an earlier stage of ventricular involvement.Restrictive and infiltrative cardiomyopathies are characterized by an increase in ventricular stiffness with ensuing diastolic dysfunction and heart failure. A variety of entities may produce this pathological disturbance with amyloidosis being the most prevalent. Storage diseases (Fabry, Gaucher, Hurler) are currently treatable and early detection of ventricular involvement is of paramount importance for successful treatment. Traditional differentiation between constrictive pericarditis (surgically manageable) and the rare cases of restrictive cardiomyopathy should be properly performed.
Book chapters on the topic "Key process parameters"
1
Zhang, Ming Yu, Qi Zhong Huang, Zhe An Su, Zhi Yong Xie, and Bo Yun Huang. "Study on Process Parameters of Multi-Factor Coupling Fields CVI." In Key Engineering Materials, 1451–54. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.1451.
Full text
2
Aiyiti, Wurikaixi, Wan Hua Zhao, Yi Ping Tang, and Bing Heng Lu. "Study on the Process Parameters of MPAW-Based Rapid Prototyping." In Key Engineering Materials, 1931–34. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.1931.
Full text
3
Lerma Valero, José R. "Key Parameters for Setting the Injection Molding Process." In Plastics Injection Molding, 178–92. München: Carl Hanser Verlag GmbH & Co. KG, 2020. http://dx.doi.org/10.3139/9781569906903.014.
Full text
4
Tao, Z., and Y. Gao. "Effects of Key Parameters on the Performance of a New In-Process Optical Measurement Method." In Key Engineering Materials, 405–10. Stafa: Trans Tech Publications Ltd., 2005. http://dx.doi.org/10.4028/0-87849-977-6.405.
Full text
5
Yamazaki, Y., T. Kinebuchi, H. Fukanuma, N. Ohno, and K. Kaise. "Deformation and Fracture Behaviors in the Freestanding APS-TBC - Effects of Process Parameters and Thermal Exposure." In Key Engineering Materials, 1935–38. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.1935.
Full text
6
Lee, Chong Mu, Choong Mo Kim, Sook Joo Kim, and Yun Kyu Park. "Enhancement of the Quality of the ZnO Thin Films by Optimizing the Process Parameters of High-Temperature RF Magnetron Sputtering." In Key Engineering Materials, 581–84. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-410-3.581.
Full text
7
Allanore, Antoine, Luis A. Ortiz, and Donald R. Sadoway. "Molten Oxide Electrolysis for Iron Production: Identification of Key Process Parameters for Largescale Development." In Energy Technology 2011, 121–29. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118061886.ch12.
Full text
8
Soni, Rahul, Ravi Pratap Singh, and Shailender Singh Bhadauria. "Disquisition of Impact of Key Electric Discharge Machining Input Parameters on Various Process Characteristics: A Review." In Modern Manufacturing Systems, 369–86. New York: Apple Academic Press, 2022. http://dx.doi.org/10.1201/9781003284024-30.
Full text
9
Sika, Robert, Adam Jarczyński, and Arkadiusz Kroma. "Methodology of Determination of Key Casting Process Parameters on DISA MATCH Automatic Moulding Line Affecting the Formation of Alloy-Mould Contact Defects." In Lecture Notes in Mechanical Engineering, 416–33. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-16943-5_36.
Full text
10
Liu, Kailong, Yujie Wang, and Xin Lai. "Data Science-Based Battery Manufacturing Management." In Data Science-Based Full-Lifespan Management of Lithium-Ion Battery, 49–90. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-01340-9_3.
Full textAbstract:
AbstractThis chapter focuses on the data science technologies for battery manufacturing management, which is a key process in the early lifespan of battery. As a complicated and long process, the battery manufacturing line generally consists of numerous intermediate stages involving strongly coupled interdependency, which would directly determine the performance of the manufactured battery. In this context, the in-depth exploration and management of different manufacturing parameters, variables, their correlation as well as effect towards the resulted property of manufactured intermediate products or final battery performance is crucial but still remains a difficult challenge. Recent advancements in data-driven analytic and related machine learning strategies raised interest in data science methods to perform effective and reasonable management of battery manufacturing.
Conference papers on the topic "Key process parameters"
1
Zhu, Xiaofang, Jingyuan Che, Yulu Hu, Quan Hu, Bin Li, Tao Huang, Xiaolin Jin, and Li Xu. "Simulation Exploration of Assembly Process and Key Parameters of TWT." In 2020 IEEE 21st International Conference on Vacuum Electronics (IVEC). IEEE, 2020. http://dx.doi.org/10.1109/ivec45766.2020.9520520.
Full text
2
Wang, Zaiying, and Zhipeng Shangguan. "Coordinated Control of Key Process Parameters in Dense Medium Coal Preparation." In 2019 International Conference on Intelligent Transportation, Big Data & Smart City (ICITBS). IEEE, 2019. http://dx.doi.org/10.1109/icitbs.2019.00124.
Full text
3
Bhagwat, Surbhi, and Vinod Kumar Mannaru. "Forging Process Modeling: Influence of Key Forging Process Parameters on Part Quality and Equipment Tonnage." In Symposium on International Automotive Technology 2017. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2017. http://dx.doi.org/10.4271/2017-26-0173.
Full text
4
Bin Wang, Mingzhe Yuan, Zhuo Wang, Haibin Yu, and Guang Zhu. "The development of soft measurement of key parameters in copper smelting process." In 2014 11th World Congress on Intelligent Control and Automation (WCICA). IEEE, 2014. http://dx.doi.org/10.1109/wcica.2014.7053138.
Full text
5
Bao, Zhenbo, Longxiang Yang, Jinxing Peng, and Fan Yang. "Analysis of Problems and Key Process Parameters in Household Biomass Gasification System." In 7th International Conference on Education, Management, Information and Mechanical Engineering (EMIM 2017). Paris, France: Atlantis Press, 2017. http://dx.doi.org/10.2991/emim-17.2017.203.
Full text
6
Zhu, Xiaofang, Jingyuan Che, Yulu Hu, Quan Hu, Tao Huang, Li Xu, and Bin Li. "Computer Aided Simulation of Assembly Process and Key Assembly Parameters of TWT." In 2020 IEEE International Conference on Plasma Science (ICOPS). IEEE, 2020. http://dx.doi.org/10.1109/icops37625.2020.9717547.
Full text
7
Kinsey, Brad, Matt Bravar, and Jian Cao. "Methodology and Model to Determine Key Process Parameters for Tailor Welded Blank Forming." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-43610.
Full textAbstract:
Tailor Welded Blanks (TWBs) offer several notable benefits compared to traditional sheet metal parts including decreased part weight, reduced manufacturing costs, increased environmental friendliness, and improved dimensional consistency. In order to take advantage of these benefits, however, designers must overcome formability concerns related to stamping TWBs and be able to accurately predict unique characteristics related to the forming of this blank type. In this research, an analytical model using a 2D cross-sectional approach was devised and implemented to predict the weld line movement and forming height for a uniform binder force TWB application. The inputs into the analytical model are the desired strain at the weld line location, the geometry of the 2D cross-section, material properties, and the frictional condition. From this information, the model predicts the stress and strain at several key locations on the 2D cross-section as well as the movement of the material in the binder area and in the formed walls.
8
Liu, Yuanqing, Ziyan Zhu, and Xianglin Zhu. "Soft sensor modeling for key parameters of marine alkaline protease MP fermentation process." In 2018 Chinese Control And Decision Conference (CCDC). IEEE, 2018. http://dx.doi.org/10.1109/ccdc.2018.8408209.
Full text
9
Guo, Hao, Lin Lin, Yancheng Lv, Jie Liu, and Changsheng Tong. "Machine Learning for Determining Key Parameters in Welding Process of Underground Engineering Equipment." In 2021 IEEE International Conference on Sensing, Diagnostics, Prognostics, and Control (SDPC). IEEE, 2021. http://dx.doi.org/10.1109/sdpc52933.2021.9563365.
Full text
10
Byrne, Kelly, William Hawker, and James Vaughan. "Effect of key parameters on the selective acid leach of nickel from mixed nickel-cobalt hydroxide." In PROCEEDINGS OF THE 1ST INTERNATIONAL PROCESS METALLURGY CONFERENCE (IPMC 2016). Author(s), 2017. http://dx.doi.org/10.1063/1.4974412.
Full textReports on the topic "Key process parameters"
1
Kuropiatnyk, D. I. Actuality of the problem of parametric identification of a mathematical model. [б. в.], December 2018. http://dx.doi.org/10.31812/123456789/2885.
Full textAbstract:
The purpose of the article is to study the possibilities of increasing the efficiency of a mathematical model by identifying the parameters of an object. A key factor for parametrization can be called the consideration of properties of the values of the model at a specific time point, which allows a deeper analysis of data dependencies and correlation between them. However, such a technique does not always work, because in advance it is impossible to predict that the parameters can be substantially optimized. In addition, it is necessary to take into account the fact that minimization reduces the values of parameters without taking into account their real physical properties. The correctness of the final values will be based on dynamically selected parameters, which allows you to modify the terms of use of the system in real time. In the development process, the values of experimentally obtained data with the model are compared, which allows you to understand the accuracy of minimization. When choosing the most relevant parameters, various minimization functions are used, which provides an opportunity to cover a wide range of theoretical initial situations. Verification of the correctness of the decision is carried out with the help of a quality function, which can identify the accuracy and correctness of the optimized parameters. It is possible to choose different types of functional quality, depending on the characteristics of the initial data. The presence of such tools during parametrization allows for varied analysis of the model, testing it on various algorithms, data volumes and conditions of guaranteed convergence of functional methods.
2
Tidwell, Vincent Carroll, George A. Backus, Elena Arkadievna Kalinina, William J. Peplinski, and David Blaine Hart. Sensitivity of the Community Land Model (CLM4.0) to key modeling parameters and modeling of key physical processes with focus on the arctic environment. Office of Scientific and Technical Information (OSTI), August 2012. http://dx.doi.org/10.2172/1051726.
Full text
3
Zhang, Cheng, and Yue Yang. Impact of adaptive design on reducing the duration of clinical trials in rare cancers: a meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, February 2022. http://dx.doi.org/10.37766/inplasy2022.2.0081.
Full textAbstract:
Review question / Objective: Whether the application of adaptive design in clinical trials of rare cancers can shorten the duration of clinical trials? Condition being studied: Currently, the development of innovative drug products (InMPs) for rare cancers faces many challenges, including the difficulty of enrolling sufficient numbers of patients from small and heterogeneous patient populations for clinical trials, and the significant risks of high financial investment, long development times and potential failure from a pharmaceutical company's perspective for rare cancer drugs due to limited knowledge of the natural history of the disease. Therefore, alternative approaches to clinical trial design are needed to conduct cost-effective, well-controlled analyses that can assess treatment effects in small, heterogeneous populations within shorter time frames. Adaptive trials, on the other hand, may be an effective solution to this problem. Adaptive clinical trials are designed to accelerate the clinical trial process by making predefined adjustments to key parameters through data accumulated at predefined time points during the trial without compromising the integrity and validity of the results.This study aims to examine the value of adaptive design in reducing the duration of clinical trials in rare cancers and encourage their wider implementation.
4
Ungar, Eugene D., Montague W. Demment, Uri M. Peiper, Emilio A. Laca, and Mario Gutman. The Prediction of Daily Intake in Grazing Cattle Using Methodologies, Models and Experiments that Integrate Pasture Structure and Ingestive Behavior. United States Department of Agriculture, July 1994. http://dx.doi.org/10.32747/1994.7568789.bard.
Full textAbstract:
This project addressed the prediction of daily intake in grazing cattle using methodologies, models and experiments that integrate pasture structure and ingestive behavior. The broad objective was to develop concepts of optimal foraging that predicted ingestive behavior and instantaneous intake rate in single and multi-patch environments and extend them to the greater scales of time and space required to predict daily intake. Specific objectives included: to determine how sward structure affects the shape of patch depletion curves, to determine if the basic components of ingestive behavior of animals in groups differs from animals alone, and to evaluate and modify our existing models of foraging behavior and heterogeneity to incorporate larger scales of time and space. Patch depletion was found to be predominantly by horizon, with a significant decline in bite weight during horizon depletion. This decline derives from bite overlap, and is more pronounced on taller swards. These results were successfully predicted by a simple bite placement simulator. At greater spatial scales, patch selection was aimed at maximizing daily digestible intake, with the between patch search pattern being non-random. The processes of selecting a feeding station and foraging at a feeding station are fundamentally different. The marginal value theorem may not be the most appropriate paradigm for predicting residence time at a feeding station. Basic components of ingestive behavior were unaffected by the presence of other animals. Our results contribute to animal production systems by improving our understanding of the foraging process, by identifying the key sward parameters that determine intake rate and by improving existing conceptual and quantitative models of foraging behavior across spatial and temporal scales.
5
Keller, David P. Quantification of “constrained” potential of ocean NETs. OceanNets, 2022. http://dx.doi.org/10.3289/oceannets_d4.1.
Full textAbstract:
This study uses an existing perturbed parameter ensemble (PPE) of simulated ocean CO2 removal (CDR) to better determine sustainable pathways of ocean-based NET deployment and to provide information to constrain the design of subsequent modelling experiments. The results show that ocean alkalinity enhancement (OAE) can only help meet SDG13 (Climate Action) when other ambitious mitigation efforts are taken. This reinforces that OAE is not a substitute for emissions reduction, but could contribute to meeting our climate goals (if other factors suggest OAE is worth doing). For SDG14 (Life Below Water), the results suggest OEA can contribute to limiting or even reversing ocean acidification. Meeting many other SDG14 objectives is closely linked to also meeting SDG13. A key recommendation is therefore, that subsequent simulations in OceanNETs should only use SDG13 compatible baseline scenarios, unless there is some specific need for process understanding at higher levels of climate change. The analysis has also determined that the idealized CDR in the PPE is not suitable for determining many socio-economic constraints and the implications that these have for meeting the SDGs. Another key recommendation is therefore, that subsequent simulations within OceanNETs should use more realistic scenarios of CDR deployment.
6
Smith, S. Jarrell, David W. Perkey, and Kelsey A. Fall. Cohesive Sediment Field Study : James River, Virginia. U.S. Army Engineer Research and Development Center, August 2021. http://dx.doi.org/10.21079/11681/41640.
Full textAbstract:
Estuaries trap much of the fine sediment delivered to them by rivers. This phenomenon presents challenges to the US Army Corps of Engineers (USACE) navigation mission, which maintains navigable waterways for waterborne commerce through estuarine regions. The USACE Regional Sediment Management Program and the USACE Norfolk District are conducting a regional sediment transport modeling study to identify cost-effective sediment management schemes in the James River, a tributary estuary of Chesapeake Bay. A key element of the sediment transport modeling study is the definition of cohesive sediment transport processes, such as erosion and settling velocity. This report describes field-based measurements of cohesive sediment erosion and settling velocity conducted in November 2017. The team conducted erosion testing on 15 cores collected throughout the tidal system. Additionally, two anchor stations were occupied to measure tidal variations in vertical distributions of suspended sediment concentration, particle size, and settling velocity. Recommended cohesive sediment transport parameters were developed from the field measurements.
7
Morin, Shai, Gregory Walker, Linda Walling, and Asaph Aharoni. Identifying Arabidopsis thaliana Defense Genes to Phloem-feeding Insects. United States Department of Agriculture, February 2013. http://dx.doi.org/10.32747/2013.7699836.bard.
Full textAbstract:
The whitefly (Bemisia tabaci) is a serious agricultural pest that afflicts a wide variety of ornamental and vegetable crop species. To enable survival on a great diversity of host plants, whiteflies must have the ability to avoid or detoxify numerous different plant defensive chemicals. Such toxins include a group of insect-deterrent molecules called glucosinolates (GSs), which also provide the pungent taste of Brassica vegetables such as radish and cabbage. In our BARD grant, we used the whitefly B. tabaci and Arabidopsis (a Brassica plant model) defense mutants and transgenic lines, to gain comprehensive understanding both on plant defense pathways against whiteflies and whitefly defense strategies against plants. Our major focus was on GSs. We produced transgenic Arabidopsis plants accumulating high levels of GSs. At the first step, we examined how exposure to high levels of GSs affects decision making and performance of whiteflies when provided plants with normal levels or high levels of GSs. Our major conclusions can be divided into three: (I) exposure to plants accumulating high levels of GSs, negatively affected the performance of both whitefly adult females and immature; (II) whitefly adult females are likely to be capable of sensing different levels of GSs in their host plants and are able to choose, for oviposition, the host plant on which their offspring survive and develop better (preference-performance relationship); (III) the dual presence of plants with normal levels and high levels of GSs, confused whitefly adult females, and led to difficulties in making a choice between the different host plants. These findings have an applicative perspective. Whiteflies are known as a serious pest of Brassica cropping systems. If the differences found here on adjacent small plants translate to field situations, intercropping with closely-related Brassica cultivars could negatively influence whitefly population build-up. At the second step, we characterized the defensive mechanisms whiteflies use to detoxify GSs and other plant toxins. We identified five detoxification genes, which can be considered as putative "key" general induced detoxifiers because their expression-levels responded to several unrelated plant toxic compounds. This knowledge is currently used (using new funding) to develop a new technology that will allow the production of pestresistant crops capable of protecting themselves from whiteflies by silencing insect detoxification genes without which successful host utilization can not occur. Finally, we made an effort to identify defense genes that deter whitefly performance, by infesting with whiteflies, wild-type and defense mutated Arabidopsis plants. The infested plants were used to construct deep-sequencing expression libraries. The 30- 50 million sequence reads per library, provide an unbiased and quantitative assessment of gene expression and contain sequences from both Arabidopsis and whiteflies. Therefore, the libraries give us sequence data that can be mined for both the plant and insect gene expression responses. An intensive analysis of these datasets is underway. We also conducted electrical penetration graph (EPG) recordings of whiteflies feeding on Arabidopsis wild-type and defense mutant plants in order to determine the time-point and feeding behavior in which plant-defense genes are expressed. We are in the process of analyzing the recordings and calculating 125 feeding behavior parameters for each whitefly. From the analyses conducted so far we conclude that the Arabidopsis defense mutants do not affect adult feeding behavior in the same manner that they affect immatures development. Analysis of the immatures feeding behavior is not yet completed, but if it shows the same disconnect between feeding behavior data and developmental rate data, we would conclude that the differences in the defense mutants are due to a qualitative effect based on the chemical constituency of the phloem sap.
8
Yaron, Zvi, Abigail Elizur, Martin Schreibman, and Yonathan Zohar. Advancing Puberty in the Black Carp (Mylopharyngodon piceus) and the Striped Bass (Morone saxatilis). United States Department of Agriculture, January 2000. http://dx.doi.org/10.32747/2000.7695841.bard.
Full textAbstract:
Both the genes and cDNA sequences encoding the b-subunits of black carp LH and FSH were isolated, cloned and sequenced. Sequence analysis of the bcFSHb and LHb5'flanking regions revealed that the promoter region of both genes contains canonical TATA sequences, 30 bp and 17 bp upstream of the transcription start site of FSHb and LHb genes, respectively. In addition, they include several sequences of cis-acting motifs, required for inducible and tissue-specific transcriptional regulation: the gonadotropin-specific element (GSE), GnRH responsive element (GRE), half sites of estrogen and androgen response elements, cAMP response element, and AP1. Several methods have been employed by the Israeli team to purify the recombinant b subunits (EtOH precipitation, gel filtration and lentil lectin). While the final objective to produce pure recombinantGtH subunits has not yet been achieved, we have covered much ground towards this goal. The black carp ovary showed a gradual increase in both mass and oocyte diameter. First postvitellogenic oocytes were found in 5 yr old fish. At this age, the testes already contained spermatozoa. The circulating LH levels increased from 0.5 ng/ml in 4 yr old fish to >5ng/ml in 5 yr old fish. In vivo challenge experiments in black carp showed the initial LH response of the pituitary to GnRH in 4 yr old fish. The response was further augmented in 5 yr old fish. The increase in estradiol level in response to gonadotropic stimulation was first noted in 4 yr old fish but this response was much stronger in the following year. In vivo experiments on the FSHb and LHb mRNA levels in response to GnRH were carried out on common carp as a model for synchronom spawning cyprinids. These experiments showed the prevalence of FSHP in maturing fish while LHP mRNA was prevalent in mature fish, especially in females. The gonadal fat-pad was found to originate from the retroperitoneal mesoderm and not from the genital ridge, thus differing from that reported in certain amphibians This tissue possibly serves as the major source of sex steroids in the immature black carp. However, such a function is taken over by the developing gonads in 4 yr old fish. In the striped bass, we described the ontogeny of the neuro-endocrine parameters along the brain-pituitary-gonadal axis during the first four years of life, throughout gonadal development and the onset of puberty. We also described the responsiveness of the reproductive axis to long-term hormonal manipulations at various stages of gonadal development. Most males reached complete sexual maturity during the first year of life. Puberty was initiated during the third year of life in most females, but this first reproductive cycle did not lead to the acquisition of full sexual maturity. This finding indicates that more than one reproductive cycle may be required before adulthood is reached. Out of the three native GnRHs present in striped bass, only sbGnRH and cGnRH II increased concomitantly with the progress of gonadal development and the onset of puberty. This finding, together with data on GtH synthesis and release, suggests that while sbGnRH and cGnRH II may be involved in the regulation of puberty in striped bass, these neuropeptides are not limiting factors to the onset of puberty. Plasma LH levels remained low in all fish, suggesting that LH plays only a minor role in early gonadal development. This hypothesis was further supported by the finding that experimentally elevated plasma LH levels did not result in the induction of complete ovarian and testicular development. The acquisition of complete puberty in 4 yr old females was associated with a rise in the mRNA levels of all GtH subunit genes, including a 218-fold increase in the mRNA levels of bFSH. mRNA levels of the a and PLH subunits increased only 11- and 8-fold, respectively. Although data on plasma FSH levels are unavailable, the dramatic increase in bFSH mRNA suggests a pivotal role for this hormone in regulating the onset and completion of puberty in striped bass. The hormonal regulation of the onset of puberty and of GtH synthesis and release was studied by chronic administration of testosterone (T) and/or an analog of gonadotropin-releasing hormone (G). Sustained administration of T+G increased the mRNA levels of the PLH subunit to the values characteristic of sexually mature fish, and also increased the plasma levels of LH. However, these changes did not result in the acceleration of sexual maturation. The mRNA levels of the bFSH subunit were slightly stimulated, but remained about 1/10 of the values characteristic of sexually mature fish. It is concluded that the stimulation of FSH gene expression and release does not lead to the acceleration of sexual maturity, and that the failure to sufficiently stimulate the bFSH subunit gene expression may underlie the inability of the treatments to advance sexual maturity. Consequently, FSH is suggested to be the key hormone to the initiation and completion of puberty in striped bass. Future efforts to induce precocious puberty in striped bass should focus on understanding the regulation of FSH synthesis and release and on developing technologies to induce these processes. Definite formulation of hormonal manipulation to advance puberty in the striped bass and the black carp seems to be premature at this stage. However, the project has already yielded a great number of experimental tools of DNA technology, slow-release systems and endocrine information on the process of puberty. These systems and certain protocols have been already utilized successfully to advance maturation in other fish (e.g. grey mullet) and will form a base for further study on fish puberty.
9
Lacerda Silva, P., G. R. Chalmers, A. M. M. Bustin, and R. M. Bustin. Gas geochemistry and the origins of H2S in the Montney Formation. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329794.
Full textAbstract:
The geology of the Montney Formation and the geochemistry of its produced fluids, including nonhydrocarbon gases such as hydrogen sulfide were investigated for both Alberta and BC play areas. Key parameters for understanding a complex petroleum system like the Montney play include changes in thickness, depth of burial, mass balance calculations, timing and magnitudes of paleotemperature exposure, as well as kerogen concentration and types to determine the distribution of hydrocarbon composition, H2S concentrations and CO2 concentrations. Results show that there is first-, second- and third- order variations in the maturation patterns that impact the hydrocarbon composition. Isomer ratio calculations for butane and propane, in combination with excess methane estimation from produced fluids, are powerful tools to highlight effects of migration in the hydrocarbon distribution. The present-day distribution of hydrocarbons is a result of fluid mixing between hydrocarbons generated in-situ with shorter-chained hydrocarbons (i.e., methane) migrated from deeper, more mature areas proximal to the deformation front, along structural elements like the Fort St. John Graben, as well as through areas of lithology with higher permeability. The BC Montney play appears to have hydrocarbon composition that reflects a larger contribution from in-situ generation, while the Montney play in Alberta has a higher proportion of its hydrocarbon volumes from migrated hydrocarbons. Hydrogen sulphide is observed to be laterally discontinuous and found in discrete zones or pockets. The locations of higher concentrations of hydrogen sulphide do not align with the sulphate-rich facies of the Charlie Lake Formation but can be seen to underlie areas of higher sulphate ion concentrations in the formation water. There is some alignment between CO2 and H2S, particularly south of Dawson Creek; however, the cross-plot of CO2 and H2S illustrates some deviation away from any correlation and there must be other processes at play (i.e., decomposition of kerogen or carbonate dissolution). The sources of sulphur in the produced H2S were investigated through isotopic analyses coupled with scanning electron microscopy, energy dispersive spectroscopy, and mineralogy by X-ray diffraction. The Montney Formation in BC can contain small discrete amounts of sulphur in the form of anhydrite as shown by XRD and SEM-EDX results. Sulphur isotopic analyses indicate that the most likely source of sulphur is from Triassic rocks, in particular, the Charlie Lake Formation, due to its close proximity, its high concentration of anhydrite (18-42%), and the evidence that dissolved sulphate ions migrated within the groundwater in fractures and transported anhydrite into the Halfway Formation and into the Montney Formation. The isotopic signature shows the sulphur isotopic ratio of the anhydrite in the Montney Formation is in the same range as the sulphur within the H2S gas and is a lighter ratio than what is found in Devonian anhydrite and H2S gas. This integrated study contributes to a better understanding of the hydrocarbon system for enhancing the efficiency of and optimizing the planning of drilling and production operations. Operators in BC should include mapping of the Charlie Lake evaporites and structural elements, three-dimensional seismic and sulphate ion concentrations in the connate water, when planning wells, in order to reduce the risk of encountering unexpected souring.
10
Prusky, Dov, Nancy P. Keller, and Amir Sherman. global regulation of mycotoxin accumulation during pathogenicity of Penicillium expansum in postharvest fruits. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7600012.bard.
Full textAbstract:
Background to the topic- Penicilliumas a postharvest pathogen and producer of the mycotoxin PAT. Penicilliumspp. are destructive phytopathogens, capable of causing decay in many deciduous fruits, during postharvest handling and storage; and the resulting losses can amount to 10% of the stored produce and the accumulation of large amounts of the mycotoxinpatulin. The overall goal of this proposal is to identify critical host and pathogen factors that modulate P. expansummycotoxin genes and pathways which are required for PAT production and virulence. Our preliminary results indicated that gluconic acid are strongly affecting patulin accumulation during colonization. P. expansumacidifies apple fruit tissue during colonization in part through secretion of gluconic acid (GLA). Several publications suggested that GLA accumulation is an essential factor in P. expansumpathogenicity. Furthermore, down regulation of GOX2 significantly reduced PAT accumulation and pathogenicity. PAT is a polyketide and its biosynthesis pathway includes a 15-gene cluster. LaeA is a global regulator of mycotoxin synthesis. It is now known that patulin synthesis might be subjected to LaeA and sometimes by environmental sensing global regulatory factors including the carbon catabolite repressor CreA as well as the pH regulator factor PacC and nitrogen regulator AreA. The mechanisms by which LaeA regulates patulin synthesis was not fully known and was part of our work. Furthermore, the regulatory system that controls gene expression in accordance with ambient pH was also included in our work. PacC protein is in an inactive conformation and is unable to bind to the promoter sites of the target genes; however, under alkaline growth conditions activated PacC acts as both an activator of alkaline-expressed genes and a repressor of acid-expressed genes. The aims of the project- This project aims to provide new insights on the roles of LaeA and PacC and their signaling pathways that lead to GLA and PAT biosynthesis and pathogenicity on the host. Specifically, our specific aims were: i) To elucidate the mechanism of pH-controlled regulation of GLA and PAT, and their contribution to pathogenesis of P. expansum. We are interested to understanding how pH and/or GLA impact/s under PacC regulation affect PAT production and pathogenesis. ii) To characterize the role of LaeA, the global regulator of mycotoxin production, and its effect on PAT and PacC activity. iii) To identify the signaling pathways leading to GLA and PAT synthesis. Using state- of-the-art RNAseq technologies, we will interrogate the transcriptomes of laeAand pacCmutants, to identify the common signaling pathways regulating synthesis of both GLA and PAT. Major conclusions, solutions, achievements- In our first Aim our results demonstrated that ammonia secreted at the leading edge of the fungal colony induced transcript activation of the global pH modulator PacC and PAT accumulation in the presence of GLA. We assessed these parameters by: (i) direct exogenous treatment of P. expansumgrowing on solid medium; (ii) direct exogenous treatment on colonized apple tissue; (iii) growth under self-ammonia production conditions with limited carbon; and (iv) analysis of the transcriptional response to ammonia of the PAT biosynthesis cluster. Ammonia induced PAT accumulation concurrently with the transcript activation of pacCand PAT biosynthesis cluster genes, indicating the regulatory effect of ammonia on pacCtranscript expression under acidic conditions. Transcriptomic analysis of pH regulated processes showed that important genes and BARD Report - Project 4773 Page 2 of 10 functionalities of P. expansumwere controlled by environmental pH. The differential expression patterns of genes belonging to the same gene family suggest that genes were selectively activated according to their optimal environmental conditions to enable the fungus to cope with varying conditions and to make optimal use of available enzymes. Concerning the second and third Aims, we demonstrated that LaeA regulates several secondary metabolite genes, including the PAT gene cluster and concomitant PAT synthesis invitro. Virulence studies of ΔlaeAmutants of two geographically distant P. expansumisolates (Pe-21 from Israel and Pe-T01 from China) showed differential reduction in disease severity in freshly harvested fruit ranging from no reduction for Ch-Pe-T01 strains in immature fruit to 15–25% reduction for both strains in mature fruit, with the ΔlaeAstrains of Is-Pe-21 always showing a greater loss in virulence. Results suggest the importance of LaeA regulation of PAT and other secondary metabolites on pathogenicity. Our work also characterized for the first time the role of sucrose, a key nutritional factor present in apple fruit, as a negative regulator of laeAexpression and consequent PAT production in vitro. This is the first report of sugar regulation of laeAexpression, suggesting that its expression may be subject to catabolite repression by CreA. Some, but not all of the 54 secondary metabolite backbone genes in the P. expansumgenome, including the PAT polyketide backbone gene, were found to be regulated by LaeA. Together, these findings enable for the first time a straight analysis of a host factor that potentially activates laeAand subsequent PAT synthesis.