The Experts below are selected from a list of 13761 Experts worldwide ranked by ideXlab platform
C F Kong - One of the best experts on this subject based on the ideXlab platform.
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clinical evaluation of the mapleson theoretical ideal fresh gas flow sequence at the start of low flow anaesthesia with isoflurane sevoflurane and desflurane
Anaesthesia, 2001Co-Authors: P C Ipyam, Y. H. Chan, C F KongAbstract:Mapleson used a computer Spreadsheet Model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE′an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE′an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE′an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE′an measurements were divided by their respective 1-MAC value. A simple two-level Model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2–20 min for PE′iso (1.042 [95% CI 0.980–1.104] and 1.044 [0.984–1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE′sevo (1.169 [1.119–1.219] and 1.143 [1.119–1.219]) and PE′des (1.305 [1.261–1.349] and 1.140 [1.098–1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE′an values close to or slightly higher than predicted in the Spreadsheet Model.
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Clinical evaluation of the Mapleson theoretical ideal fresh gas flow sequence at the start of low‐flow anaesthesia with isoflurane, sevoflurane and desflurane*
Anaesthesia, 2001Co-Authors: Y. H. Chan, C F KongAbstract:Mapleson used a computer Spreadsheet Model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE′an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE′an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE′an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE′an measurements were divided by their respective 1-MAC value. A simple two-level Model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2–20 min for PE′iso (1.042 [95% CI 0.980–1.104] and 1.044 [0.984–1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE′sevo (1.169 [1.119–1.219] and 1.143 [1.119–1.219]) and PE′des (1.305 [1.261–1.349] and 1.140 [1.098–1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE′an values close to or slightly higher than predicted in the Spreadsheet Model.
Raymond R Panko - One of the best experts on this subject based on the ideXlab platform.
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Hitting the wall: errors in developing and code inspecting a 'simple' Spreadsheet Model
Decision Support Systems, 1998Co-Authors: Raymond R Panko, Ralph H. SpragueAbstract:Abstract Field audits and experiments have found substantial error rates when students and professionals have built Spreadsheet Models. In this study, 102 undergraduate MIS majors and 50 MBA students developed a Model from a word problem that was relatively simple and free of domain knowledge. Even so, 35% of their 152 Models were incorrect. There was no significant difference in errors per Model between undergraduates and MBAs. Even among the 17 MBAs with 250 h or more of experience, 24% of the Models contained errors. The cell error rate (CER)—the percentage of cells with errors—was 2.0%. When 23 undergraduates attempted to audit their Models through code inspection, only three with incorrect Spreadsheets (15%) produced clean Spreadsheets when they finished the audit.
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hitting the wall errors in developing and debugging a simple Spreadsheet Model
Hawaii International Conference on System Sciences, 1996Co-Authors: Raymond R PankoAbstract:Undergraduate MIS business students developed and debugged a Spreadsheet Model from a word problem. This Model consisted of a bid to build a wall. The problem was designed to be relatively simple and domain-free to address the concern that past Spreadsheet experiments may have used problems that were too difficult or that required domain knowledge that subjects did not have. During the development phase, 72 subjects created the Spreadsheet Model. Even with this rather simple problem, 38% of the Models contained an error. This high number of incorrect Spreadsheets was not due to subjects making many errors. They only made 0.4 errors per Spreadsheet. In addition, their cell error rate (CER) was only 1.7%, meaning that only 1.7% of their cells contained errors. Unfortunately, Spreadsheets tend to have long cascades of cells leading to the bottom line. This means that even tiny cell error rates will multiply into high rates of bottom-line errors. In a debugging phase, subjects tried to debug their own Models. Of 19 subjects with incorrect Models who did the debugging part of the experiment, only three (16%) found and corrected their errors. So even with a relatively simple Model, development and debugging were problematic. This is a fewer rate of finding errors than (Galletta et al., 1993; 1996) found when subjects debugged Models created by the experimenter. This may mean that people are not as good at debugging their own Models as they are at debugging Models created by others.
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HICSS (2) - Hitting the wall: errors in developing and debugging a "simple" Spreadsheet Model
Proceedings of HICSS-29: 29th Hawaii International Conference on System Sciences, 1996Co-Authors: Raymond R PankoAbstract:Undergraduate MIS business students developed and debugged a Spreadsheet Model from a word problem. This Model consisted of a bid to build a wall. The problem was designed to be relatively simple and domain-free to address the concern that past Spreadsheet experiments may have used problems that were too difficult or that required domain knowledge that subjects did not have. During the development phase, 72 subjects created the Spreadsheet Model. Even with this rather simple problem, 38% of the Models contained an error. This high number of incorrect Spreadsheets was not due to subjects making many errors. They only made 0.4 errors per Spreadsheet. In addition, their cell error rate (CER) was only 1.7%, meaning that only 1.7% of their cells contained errors. Unfortunately, Spreadsheets tend to have long cascades of cells leading to the bottom line. This means that even tiny cell error rates will multiply into high rates of bottom-line errors. In a debugging phase, subjects tried to debug their own Models. Of 19 subjects with incorrect Models who did the debugging part of the experiment, only three (16%) found and corrected their errors. So even with a relatively simple Model, development and debugging were problematic. This is a fewer rate of finding errors than (Galletta et al., 1993; 1996) found when subjects debugged Models created by the experimenter. This may mean that people are not as good at debugging their own Models as they are at debugging Models created by others.
Y. H. Chan - One of the best experts on this subject based on the ideXlab platform.
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clinical evaluation of the mapleson theoretical ideal fresh gas flow sequence at the start of low flow anaesthesia with isoflurane sevoflurane and desflurane
Anaesthesia, 2001Co-Authors: P C Ipyam, Y. H. Chan, C F KongAbstract:Mapleson used a computer Spreadsheet Model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE′an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE′an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE′an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE′an measurements were divided by their respective 1-MAC value. A simple two-level Model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2–20 min for PE′iso (1.042 [95% CI 0.980–1.104] and 1.044 [0.984–1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE′sevo (1.169 [1.119–1.219] and 1.143 [1.119–1.219]) and PE′des (1.305 [1.261–1.349] and 1.140 [1.098–1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE′an values close to or slightly higher than predicted in the Spreadsheet Model.
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Clinical evaluation of the Mapleson theoretical ideal fresh gas flow sequence at the start of low‐flow anaesthesia with isoflurane, sevoflurane and desflurane*
Anaesthesia, 2001Co-Authors: Y. H. Chan, C F KongAbstract:Mapleson used a computer Spreadsheet Model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE′an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE′an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE′an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE′an measurements were divided by their respective 1-MAC value. A simple two-level Model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2–20 min for PE′iso (1.042 [95% CI 0.980–1.104] and 1.044 [0.984–1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE′sevo (1.169 [1.119–1.219] and 1.143 [1.119–1.219]) and PE′des (1.305 [1.261–1.349] and 1.140 [1.098–1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE′an values close to or slightly higher than predicted in the Spreadsheet Model.
Jácome Cunha - One of the best experts on this subject based on the ideXlab platform.
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Embedding Model-driven Spreadsheet queries in Spreadsheet systems
Proceedings of IEEE Symposium on Visual Languages and Human-Centric Computing VL HCC, 2014Co-Authors: Jácome Cunha, Jorge Mendes, Rui Pereira, João Paulo Fernandes, João SaraivaAbstract:Spreadsheets are widely used not only to define mathematical expressions, but also to store large and complex data. To query such data is usually a difficult task to perform, usually for end user. In this work we embed the textual query language in the Model-driven Spreadsheet environment as a Spreadsheet itself. The result is an expressive and powerful query environment that has knowledge of the business logic defined by the Spreadsheet data (the Spreadsheet Model) to guide end users constructing correct queries.
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VL/HCC - Embedding Model-Driven Spreadsheet Queries in Spreadsheet Systems
2014 IEEE Symposium on Visual Languages and Human-Centric Computing (VL HCC), 2014Co-Authors: Rui Pereira, Jorge Mendes, João Paulo Fernandes, João Saraiva, Jácome CunhaAbstract:Spreadsheets are widely used not only to define mathematical expressions, but also to store large and complex data. To query such data is usually a difficult task to perform, usually for end user. In this work we embed the textual query language in the Model-driven Spreadsheet environment as a Spreadsheet itself. The result is an expressive and powerful query environment that has knowledge of the business logic defined by the Spreadsheet data (the Spreadsheet Model) to guide end users constructing correct queries.
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a bidirectional Model driven Spreadsheet environment
International Conference on Software Engineering, 2012Co-Authors: Jácome Cunha, Jorge Mendes, João Paulo Fernandes, João SaraivaAbstract:In this extended abstract we present a bidirectional Model-driven framework to develop Spreadsheets. By being Model driven, our approach allows to evolve a Spreadsheet Model and automatically have the data co-evolved. The bidirectional component achieves precisely the inverse, that is, to evolve the data and automatically obtain a new Model to which the data conforms.
John Kropp - One of the best experts on this subject based on the ideXlab platform.
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Studying the operational efficiencies of a multi-product supply chain using excel Spreadsheet Model
Technovation, 2006Co-Authors: Sameer Kumar, John KroppAbstract:Abstract This paper presents a simple Excel Spreadsheets-based Model with @Risk add-in software that incorporates the effects of variability in demand, forecast and lead time. The Model replicates a four-stage supply chain with multiple-retailers, wholesalers, manufacturers, and suppliers to demonstrate how a multi-product supply chain will react to certain changes. The Model was created so that it could be used in either a teaching setting or in industry for making supply chain design decisions. From the teaching aspect, students can look at a supply chain and see the effects of changes without having to experience it firsthand. Professionals in industry can modify the Model to make it more like their own supply chain and see what the affects are when they want to make changes in one or more attributes. Other key characteristics of a supply chain such as, bullwhip effect, total supply chain cost analysis and information sharing can also be studied using this Model.