Comparative Analysis of Supply Chain Management Practices by Boeing and Airbus: Long-Term Strategic Implications

Research Goals and Approach: Goals - • Develop an improved understanding of emerging supply chain management strategies and practices in the commercial aerospace industry • Explore the longer-term implications of the findings for supply chain management practices in the aerospace industry in the future/ Approach - • Conduct a comparative analysis of supply chain management practices by Boeing and Airbus • Focus on two large development programs -- the Boeing 787 Dreamliner and the Airbus A380 Navigator • Concentrate on the common set of suppliers supporting both programs to develop a sharp “compare-and contrast” perspective, looking at Boeing & Airbus from the vantage point of these common suppliers • Capture bottom-up “supplier’s voice” to complement “top-down” perspective, while controlling for any “embellished” top-down view from the two companie

A comparative analysis of supply chain management practices by Boeing and Airbus : long-term strategic implications

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2007.Includes bibliographical references (p. 127-131).The goal of this research is to develop an improved understanding of supply chain management strategies and practices being pursued by Boeing and Airbus in the 787 Dreamliner and the A380 Navigator programs, respectively, and to identify their long-term strategic implications for supply chain management in the future. The research takes as its point of departure a review and synthesis of supply chain management principles and practices, with particular emphasis on lean supply chain management concepts. Guided by this review, the research focuses on the common set of suppliers supporting both programs and employs a questionnaire survey, followed by telephone interviews with representatives of selected suppliers. The research also makes extensive use of the open source information on both companies, on both programs and on the common suppliers.(cont.) A major finding is that Boeing's new supply chain model in the 787 program represents a significant break with past practices in the aerospace industry, allowing major partnering suppliers an unprecedented role in terms of design, development, production and after-market support, where they are integrated early in the concept development stage and are incentivized to collaborate with Boeing, as well as among themselves, as risk-sharing partners with deep responsibility for system integration, involving detailed interface control at the system and subsystem levels. Airbus, as well, is found to rely heavily on its major suppliers in connection with the A380 program, but acting as the primary system integrator in the more traditional mode and exercising much greater control of all design interfaces. Also, both Boeing and Airbus have been outsourcing more and more activities to suppliers located in non-traditional regions, such as Eastern Europe and the Asia-Pacific region. Finally, aerospace manufacturers, in general, are aggressively adopting information technologies (e.g., EDI, PLM, 3-D Digital Model, RFID) to facilitate greater data sharing and communications with their partners and lower-tier suppliers dispersed in many geographical regions, as part of a broader trend involving more collaborative supplier relationships reaching down to the subtier level.by Tzu-Ching Horng.S.M

Inferring Queueing Network Models from High-precision Location Tracking Data

Stochastic performance models are widely used to analyse the performance and reliability of systems that involve the flow and processing of customers. However, traditional methods of constructing a performance model are typically manual, time-consuming, intrusive and labour-intensive. The limited amount and low quality of manually-collected data often lead to an inaccurate picture of customer flows and poor estimates of model parameters. Driven by advances in wireless sensor technologies, recent real-time location systems (RTLSs) enable the automatic, continuous and unintrusive collection of high-precision location tracking data, in both indoor and outdoor environment. This high-quality data provides an ideal basis for the construction of high-fidelity performance models. This thesis presents a four-stage data processing pipeline which takes as input high-precision location tracking data and automatically constructs a queueing network performance model approximating the underlying system. The first two stages transform raw location traces into high-level “event logs” recording when and for how long a customer entity requests service from a server entity. The third stage infers the customer flow structure and extracts samples of time delays involved in the system; including service time, customer interarrival time and customer travelling time. The fourth stage parameterises the service process and customer arrival process of the final output queueing network model. To collect large-enough location traces for the purpose of inference by conducting physical experiments is expensive, labour-intensive and time-consuming. We thus developed LocTrack- JINQS, an open-source simulation library for constructing simulations with location awareness and generating synthetic location tracking data. Finally we examine the effectiveness of the data processing pipeline through four case studies based on both synthetic and real location tracking data. The results show that the methodology performs with moderate success in inferring multi-class queueing networks composed of single-server queues with FIFO, LIFO and priority-based service disciplines; it is also capable of inferring different routing policies, including simple probabilistic routing, class-based routing and shortest-queue routing

Whole-body vibration training effect on physical performance and obesity in mice

The purpose of this study was to verify the beneficial effects of whole-body vibration (WBV) training on exercise performance, physical fatigue and obesity in mice with obesity induced by a high-fat diet (HFD). Male C57BL/6 mice were randomly divided into two groups: normal group (n=6), fed standard diet (control), and experimental group (n=18), fed a HFD. After 4-week induction, followed by 6-week WBV of 5 days per week, the 18 obese mice were divided into 3 groups (n=6 per group): HFD with sedentary control (HFD), HFD with WBV at relatively low-intensity (5.6 Hz, 0.13 g) (HFD+VL) or high-intensity (13 Hz, 0.68 g) (HFD+VH). A trend analysis revealed that WBV increased the grip strength in mice. WBV also dose-dependently decreased serum lactate, ammonia and CK levels and increased glucose level after the swimming test. WBV slightly decreased final body weight and dose-dependently decreased weights of epididymal, retroperitoneal and perirenal fat pads and fasting serum levels of alanine aminotransferase, CK, glucose, total cholesterol and triacylglycerol. Therefore, WBV could improve exercise performance and fatigue and prevent fat accumulation and obesity-associated biochemical alterations in obese mice. It may be an effective intervention for health promotion and prevention of HFD-induced obesity

Gamma Ray and Radon Anomalies in Northern Taiwan as a Possible Preearthquake Indicator around the Plate Boundary

Taiwan is tectonically situated in an oblique collision zone between the Philippine Sea Plate (PSP) and the Eurasian Plate (EP). Continuous observations of gamma rays at the Yangmingshan (YMSG) station and soil radon at the Tapingti (TPT) station were recorded in the volcanic area and around a major fault zone, respectively, in Taiwan for seismic studies. A number of anomalous high gamma ray counts and radon concentrations at certain times were found. It is noted that significant increases of soil radon concentrations were observed and followed by the increase in gamma rays a few days to a few weeks before earthquakes that occurred in northeastern Taiwan. Earthquakes such as these are usually related to the subduction of the PSP beneath the EP to the north along the subduction zone in northern Taiwan (e.g., ML = 6 4, April 20, 2015). It is suggested that the preseismic activity may be associated with slow geodynamic processes at the subduction interface, leading to the PSP movement triggering radon enhancements at the TPT station. Furthermore, the further movement of the PSP might be blocked by the EP, with the accumulated elastic stress resulting in the increase of gamma rays due to the increase in porosity and fractures below the YMSG station. The continuous monitoring of the multiple parameters can improve the understanding of the relationship between the observed radon and gamma ray variations and the regional crustal stress/strain in north and northeastern Taiwan

Hyperbaric oxygen therapy as rescue therapy for pediatric frosted branch angiitis with Purtscher-like retinopathy: A case report

IntroductionFrosted branch angiitis (FBA) is an uncommon uveitis characterized by fulminant retinal vasculitis. Purtscher-like retinopathy (PuR) is a rare retinal angiopathy associated with a non-traumatic etiology. Both FBA and PuR can cause profound visual impairments.Case reportWe describe the case of a 10-year-old male who presented with sudden bilateral painless visual loss due to FBA with concurrent PuR, with notable viral prodrome 1 month prior to presentation. Systemic investigations revealed a recent herpes simplex virus 2 infection with a high titer of IgM, positive antinuclear antibody (ANA) (1:640), and abnormal liver function tests. After administration of systemic corticosteroids, anti-viral agents, and subsequent immunosuppressive medications, the FBA was gradually alleviated. However, fundoscopy and optical coherence tomography (OCT) revealed persistent PuR and macular ischemia. Hence, hyperbaric oxygen therapy was administered as a rescue strategy, which resulted in gradual bilateral visual acuity improvement.ConclusionHyperbaric oxygen therapy may be a beneficial rescue treatment for retinal ischemia secondary to FBA with PuR

Pre-Operative Risk Factors Predict Post-Operative Respiratory Failure after Liver Transplantation

OBJECTIVE: Post-operative pulmonary complications significantly affect patient survival rates, but there is still no conclusive evidence regarding the effect of post-operative respiratory failure after liver transplantation on patient prognosis. This study aimed to predict the risk factors for post-operative respiratory failure (PRF) after liver transplantation and the impact on short-term survival rates. DESIGN: The retrospective observational cohort study was conducted in a twelve-bed adult surgical intensive care unit in northern Taiwan. The medical records of 147 liver transplant patients were reviewed from September 2002 to July 2007. Sixty-two experienced post-operative respiratory failure while the remaining 85 patients did not. MEASUREMENTS AND MAIN RESULTS: Gender, age, etiology, disease history, pre-operative ventilator use, molecular adsorbent re-circulating system (MARS) use, source of organ transplantation, model for end-stage liver disease score (MELD) and Child-Turcotte-Pugh score calculated immediately before surgery were assessed for the two groups. The length of the intensive care unit stay, admission duration, and mortality within 30 days, 3 months, and 1 year were also evaluated. Using a logistic regression model, post-operative respiratory failure correlated with diabetes mellitus prior to liver transplantation, pre-operative impaired renal function, pre-operative ventilator use, pre-operative MARS use and deceased donor source of organ transplantation (p<0.05). Once liver transplant patients developed PRF, their length of ICU stay and admission duration were prolonged, significantly increasing their mortality and morbidity (p<0.001). CONCLUSIONS: The predictive pre-operative risk factors significantly influenced the occurrence of post-operative respiratory failure after liver transplantation

Deriving Generalised Stochastic Petri Net performance models from High-Precision Location Tracking Data

Stochastic performance models have been widely used to analyse the performance and reliability of systems that involve the flow and processing of customers and/or resources with multiple service centres. However, the quality of performance analysis delivered by a model depends critically on the degree to which the model accurately represents the operations of the real system. This paper presents an automatedtechniquewhichtakesasinputhigh-precisionlocation tracking data – potentially collected from a real life system – and constructs a hierarchical Generalised Stochastic Petri Net performance model of the underlying system. We examine our method’s effectiveness and accuracy through two case studies based on synthetic location tracking data