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X bar-S square區域管制圖的最適設計 / The Optimal Design of X bar-S Square Zone Control Charts陳智鴻, Chen, Chih-Hon Unknown Date (has links)
自Duncan在1956年提出管制圖的經濟設計以來,陸續有許多學者提出各種不同型態管制圖的經濟設計,但是在這些文章中,尚無將描點的連串檢定列入考慮者,然而在管制圖中加入描點的連串檢定實有其必要性,加入描點的連串檢定可增加管制圖的偵測能力,但是這種作法頗為麻煩,因此Jaehn(1987)提出了區域管制圖來取代傳統管制圖加上連串檢定的不便,本研究提出X Bar-S Square 區域管制圖的經濟設計以改善一般經濟管制圖未將描點的連串檢定列入考慮的缺點.我們以製程中各項製程和成本資料為因子,對經濟區域管制圖的最佳設計參數值做敏感度分析,以找出製程中的關鍵參數.另外我們應用Saniga(1989)經濟統計管制圖的觀念設計經濟統計區域管制圖.雖然經濟統計區域管制圖所計算出的成本會比經濟區域管制圖稍大,但是在統計表現上卻符合我們的要求.
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少量連串下最適設計參數值之決定 / The Decision of the Best Fitted Design Parameters on Small Runs嚴珮文, Yen, Pay Wen Unknown Date (has links)
管制圖之經濟模型首由Duncan(1956)提出,自此之後陸續有學者致力研究經濟管制圖,包括X-bar管制圖、S管制圖等。但R管制圖之經濟設計目前尚無人提出。而在實務上,部份產業可能由於產品過於昂貴,或者產品的製造時間所需甚長,而使得品檢時所抽取的樣本數無法達到25個,這時若採用傳統的管制圖來分析製程,將無法顯示製程真正的狀態。因此本研究首先探討少量連串下X-bar和R管制圖之製作原理,並計算及整理出較完整的少量連串下X-bar和R的管制係數表。接著假設非機遇因素只影響製程運用Banerjee和Rahim(1987)的更新理論方法,建立少量連串情形下的R經濟管制圖。再利用最佳化方法,即可求得最適設計參數值。於是,少量連串情形下的R經濟管制圖得以建立。最後,我們將舉一個例子來說明如何獲得最適設計參數值、決定關鍵參數,以及少量連串情形下R經濟管制圖之建立與應用。
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S管制圖之經濟設計:更新理論方法 / Economic Design of S Control Chart : A Renewal Theory Approach鄭明芳, Jeng, Ming Fang Unknown Date (has links)
管制圖設計的經濟模式在最近三十年已經被廣泛的研究。本研究利用更新
理論方法(Renewal Theory Approach) 解出兩個非隨機因素下之S 經濟管
制圖。與其它的多重非隨機因素製程模式相比較,我們的模式不僅假設更
合理且以此方法表示平均循環時間(The Expected Cycle Time) 及平均循
環成本(The Expected Cycle Cost)會比擴展Duncan的方法或其它的方法
簡單容易。文中以數值例子說明建立 S 經濟管制圖的過程,並比較 S經
濟管制圖與Shewhart S 管制圖成本的大小及偵錯能力。另外,當製程上
有多重非隨機因素發生時,其成本模式也可容易的以更新理論方法擴展而
得。在實務上,若業者希望以最小成本維持製程之穩定,則可依本文所提
出的方法建立經濟管制圖。
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捲積管制圖之設計 / The design of the convolution chart鄭鈞遠, Cheng, Chun-Yuan Unknown Date (has links)
量測誤差是工業製程中影響產品值常見的因素。大的量測誤差會使得產品的量測值偏離實際值,並引導監控者至錯誤的結論。本文提出一種新的捲積管制圖。提出指數分配形式的時間間隔型資料,並加上量測誤差的考量,應用在指數加權移動平均管制圖上。此外,假設量測誤差為常態或是指數分配。研究顯示出,在兩種不同分配的量測誤差之下,管制圖的表現都會顯著的受到影響。 / Measurement error is an important factor in industry that influences the outcome of a process. Large measurement error would cause the observation measure deviate from the true value and consequently lead to a wrong decision. In this project, we propose a convolution control chart. We then design the EWMA ‘time between events’ (TBE) control chart with the measurement error, with the assumption that the observations are exponentially distributed. In addition, we assumed the measurement error follows a normal distribution or an exponential distribution. We showed that, in two cases of the measurement error, the performance of the proposed chart monitoring the process mean is greatly affected.
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The Effectiveness of the Hybrid Graphical Representation Method in Visually Combining and Communicating Logical and Spatial Relationships between Scheduled ActivitiesNageeb, Meena 2012 May 1900 (has links)
This research endeavor investigated the possibility to combine the visual advantages of both graphical schedule visualization methods, the Linked Gantt Charts (LGC) and Flowline graphs (FLG), derived from the activity-based and location-based scheduling systems, to help resolve some of their shortcomings by capitalizing on their combined strengths. In order to accomplish the goal of the research, a graphical representation system that combines these two scheduling visualization methods, LGC and FLG, is developed. Afterwards, the research attempted to empirically validate the ability of the proposed tool to visually communicate and combine logical and spatial relationships between scheduled activities. This is compared to comprehending the same information by looking at a stand-alone LGC or FLG. The accuracy and time, of deciphering various details of a sample project schedule, are used as parameters to evaluate the proposed scheduling visualization tool, and compare it to the existing LGC and FLG systems.
The Hybrid Graphical Representation (HGR) is the tool developed by this research to combine Linked Gantt Chart bars from the activity-based scheduling approach, and flow-lines from the location-based scheduling approach. The HGR concept is founded on the basic idea that both LGC and FLG share a common X-axis, Time. The only difference is in a LGC the Activities are listed on the Y-axis, while the FLG shows Locations on the Y-axis. This research proposed adding a third dimension to the FLG, listing the project Activities on a Z-axis. Viewing the HGR 3D graph from the top, the user will observe the Gantt bars with Time on the X-axis and the Activities listed on the Z-axis. Observing the schedule from the front view, the user will see the flow-lines developed from the location-based scheduling approach with Locations on the Y-axis and Time on the X-axis. After conducting a series of online surveys measuring the time and accuracy of using a prototype HGR schedule, it was found that the users were able to reap the benefits of both scheduling approaches (LGC and FLG), and visually link and communicate information concerning the activities' logical relationships and spatial relationships. However, it took the participants a relatively longer time to achieve that higher accuracy utilizing the HGR tool.
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Review and Approval Process -An Operation Development Project at ABB FACTS R&DBånghammar, Malin, Norling, Marie January 2012 (has links)
ABB is a global leader in Power and Automation Technologies. This Theses Work has been carried out at ABB FACTS R&D Department in Västerås. ABB FACTS intend to develop new Product Platforms that is partly accomplished with new methods and processes. This Master Thesis concerns the development of a generic Review and Approval Process for these R&D Projects. The development of the generic Review and Approval process is mostly founded on several interviews of employees at ABB FACTS. The respondents are employees from several departments with different amount of experiences and background. In addition to the interviews a Literature Study focused on Roles and Responsibilities, Document Management and R&D Processes was performed. Information in connection to the problem statements concerning Responsibility- and Project Roles in R&D projects and Review and Approval Execution was collected and analyzed during the project. Information regarding how to demonstrate Roles and Responsibilities in relation to the project participants was also considered. The result of this project consists of a Responsibility Chart where all R&D Project related Document Types are listed in relation to the defined Project Roles. This Responsibility Chart also display what responsibility every Project Role has regarding review and approval related to the Document Types. Besides the Responsibility Chart also other objects were developed, such as a Review Record, a Process Description and a User Guide. The above mentioned results are developed in close cooperation with several R&D Project Managers. Furthermore the expectations are that the developed result will be taken in usage and thereby continuously be revised and improved in order to suit the organization to maximum extent.
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Tillämpning av Toyotas produktionssystem på Electrolux Distriparts ABMath, Björn, Math, Jonas January 2006 (has links)
Uppgiften som låg till grund för denna uppsats, var att ge förslag på produktivitetshöjande åtgärder på Electrolux Distriparts godsmottagning. Vår avsikt var att tillämpa delar av Toyotas produktionssystem på den befintliga processen. Detta resulterade i en serie förslag som, om de tillämpas, drastiskt kommer höja produktiviteten i den aktuella processen. / The task, which is the basis of this report, was to suggest some productivity-raising actions for the incoming goods departments at Electrolux Distriparts. The project set out to utilise parts of the Toyota production model in the existing process. This resulted in a series of suggestions, which if implemented, would drastically increase the productivity of the relevant process.
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An Advisory System For Selecting Drilling Technologies and Methods in Tight Gas ReservoirsPilisi, Nicolas 16 January 2010 (has links)
The supply and demand situation is crucial for the oil and gas industry during the first half of the 21st century. For the future, we will see two trends going in opposite directions: a decline in discoveries of conventional oil and gas reservoirs and an increase in world energy demand. Therefore, the need to develop and produce unconventional oil and gas resources, which encompass coal-bed methane, gas-shale, tight sands and heavy oil, will be of utmost importance in the coming decades. In the past, large-scale production from tight gas reservoirs occurred only in the U.S. and was boosted by both price incentives and well stimulation technology. A conservative study from Rogner (1997) has shown that tight gas sandstone reservoirs would represent at least over 7,000 trillion cubic feet (Tcf) of natural gas in place worldwide. However, most of the studies such as the ones by the U.S. Geological Survey (U.S.G.S.) and Kuuskraa have focused on assessing the technically recoverable gas resources in the U.S. with numbers ranging between 177 Tcf and 379 Tcf.
During the past few decades, gas production from tight sands field developments have taken place all around the world from South America (Argentina), Australia, Asia (China, Indonesia), the Russian Federation, Northern Europe (Germany, Norway) and the Middle East (Oman). However, the U.S. remains the region where the most extensive exploration and production for unconventional gas resources occur. In fact, unconventional gas formations accounted for 43% of natural gas production and tight gas sandstones represented 66% of the total of unconventional resources produced in the U.S. in 2006. As compared to a conventional gas well, a tight gas well will have a very low productivity index and a small drainage area. Therefore, to extract the same amount of natural gas out of the reservoir, many more wells will have to be drilled and stimulated to efficiently develop and produce these reservoirs. Thus, the risk involved is much higher than the development of conventional gas resources and the economics of developing most tight gas reservoirs borders on the margin of profitability. To develop tight gas reservoirs, engineers face complex problems because there is no typical tight gas field. In reality, a wide range of geological and reservoir differences exist for these formations. For instance, a tight gas sandstone reservoir can be shallow or deep, low or high pressure, low or high temperature, bearing continuous (blanket) or lenticular shaped bodies, being naturally fractured, single or multi-layered, and holding contaminants such as CO2 and H2S which all combined increase considerably the complexity of how to drill a well.
Since the first tight gas wells were drilled in the 1940's in the U.S., a considerable amount of information has been collected and documented within the industry literature. The main objective of this research project is to develop a computer program dedicated to applying the drilling technologies and methods selection for drilling tight gas sandstone formations that have been documented as best practices in the petroleum literature.
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Robust Control ChartsCetinyurek, Aysun 01 January 2007 (has links) (PDF)
ABSTRACT
ROBUST CONTROL CHARTS
Ç / etinyü / rek, Aysun
M. Sc., Department of Statistics
Supervisor: Dr. BariS Sü / rü / cü / Co-Supervisor: Assoc. Prof. Dr. Birdal Senoglu
December 2006, 82 pages
Control charts are one of the most commonly used tools in statistical process
control. A prominent feature of the statistical process control is the Shewhart
control chart that depends on the assumption of normality. However, violations of
underlying normality assumption are common in practice. For this reason, control
charts for symmetric distributions for both long- and short-tailed distributions are
constructed by using least squares estimators and the robust estimators -modified
maximum likelihood, trim, MAD and wave. In order to evaluate the performance
of the charts under the assumed distribution and investigate robustness properties,
the probability of plotting outside the control limits is calculated via Monte Carlo
simulation technique.
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A Study of Quality Management in Health Care-Vital Signs Monitoring Process at ICUChow, Kim-Jean 19 July 2000 (has links)
Total quality management (TQM) approach is often used to carry out company-wide continuous quality improvement plans in manufacturing and service industries. Similarly, TQM can also play a critical role for quality management in health care. Aiming to improve health care quality, experiences showed that major problems of non-patient care, patient records and vital signs monitoring are encountered. In this study, we aim to introduce TQM for quality improvement for intensive care unit (ICU) operations, including some solutions and the prototype of quality management. And vital signs monitoring at ICU is taken as an example of process.
For quality improvement of non-patient care, Health Care Quality Development Life Cycle, including (1) quality requirement analysis, (2) quality specification review, (3) quality design, (4) quality implementation, (5) quality testing, (6) quality maintaining, and (7) quality validation, is discussed. The prototype of the first three phases for quality improvement at ICU is explored. Through quality requirement analysis, non-patient care quality at ICU is defined in areas of administration, facility and environment.
For quality improvement of patient records maintaining, firstly, scope of health care information systems is categorized as administrative operational system, decision support system, clinical information system, and medical information system. According to this categorization and experience, some interesting result is found. For instance, the current applications of information systems for teaching hospitals in southern Taiwan surveyed are that most applications are administrative and clinical. And the essential information of patient records used in each information system is not complete or not easily accessed. Model of the patient record maintaining is introduced and the prototype design of patient records is recommended for quality improvement of patient records maintaining at ICU.
To improve quality of vital signs monitoring is one essential requirement and specification for ICU quality improvement. Effective outcome measures of vital signs monitoring and early detecting of abnormal vital signs is considered important. For quality improvement of vital signs monitoring at ICU, heart rate graphs are taken as examples in our study through the heart rate graphs monitoring. Health professionals can understand the interactions of human autonomic nervous system. By use of digitizer, the computable heart rate data is acquired from each graph and grouped into mortality and near-to-normal cases. Then spectrum form of heart rate data, describing more about heart function, is used for statistical analysis. Several control chart methods have been experimented to detect small heart rate shifts from target, cumulative sum control chart (Cusum) is adopted in our study. The observable variable is the patient¡¦s heart rate, the purpose is to check the alarms pointed out by Cusum that could be partially be ascribed to changes of heart rate trend over time, and to a shift in the monitoring process mean. From summaries of nonconformities in the Cusum charts, mortality cases obviously have more nonconformities. It is obvious that Cusum control charts of mortality cases provide diagnostic information for vital signs monitoring process. In addition, Cusum charts may also inform ICU professionals that there is a small shift of patient heart rate, a continuously increasing or decreasing heart rate, and the adjustment of sympathetic nerve and parasympathetic nerve. In those cases, some special care is needed.
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