A Framework of Working Across Disciplines in Early Design and R&D of Large Complex Engineered Systems

This paper examines four primary methods of working across disciplines during R&D and early design of large-scale complex engineered systems such as aerospace systems. A conceptualized framework, called the Combining System Elements framework, is presented to delineate several aspects of cross-discipline and system integration practice. The framework is derived from a theoretical and empirical analysis of current work practices in actual operational settings and is informed by theories from organization science and engineering. The explanatory framework may be used by teams to clarify assumptions and associated work practices, which may reduce ambiguity in understanding diverse approaches to early systems research, development and design. The framework also highlights that very different engineering results may be obtained depending on work practices, even when the goals for the engineered system are the same

MDO and Cross-Disciplinary Practice in R&D: A Portrait of Principles and Current Practice

For several decades, Multidisciplinary Design Optimization (MDO) has served an important role in aerospace engineering by incorporating physics based disciplinary models into integrated system or sub-system models for use in research, development, (R&D) and design. This paper examines MDO's role in facilitating the integration of the researchers from different single disciplines during R&D and early design of large-scale complex engineered systems (LaCES) such as aerospace systems. The findings in this paper are summarized from a larger study on interdisciplinary practices and perspectives that included considerable empirical data from surveys, interviews, and ethnography. The synthesized findings were derived by integrating the data with theories from organization science and engineering. The over-arching finding is that issues related to cognition, organization, and social interrelations mostly dominate interactions across disciplines. Engineering issues, such as the integration of hardware or physics-based models, are not as significant. Correspondingly, the data showed that MDO is not the primary integrator of researchers working across disciplines during R&D and early design of LaCES. Cognitive focus such as analysis versus design, organizational challenges such as incentives, and social opportunities such as personal networks often drove the human interactive practices among researchers from different disciplines. Facilitation of the inherent confusion, argument, and learning in crossdisciplinary research was identified as one of several needed elements of enabling successful research across disciplines

Serous cystadenocarcinoma of the pancreas: report of a case and management reflections

<p>Abstract</p> <p>Background</p> <p>Serous adenomas represent 1-2% of pancreatic neoplasms and typically are asymptomatic not requiring any treatment and simple observation is the option of choice. Although, they carry a realistic risk of malignancy despite the general view that they never become malignant. We report a case, which, according to our best knowledge is the 27th case reported in the literature.</p> <p>Methods</p> <p>We reviewed the literature by performing a search in Pub Med and Medline.</p> <p>Results</p> <p>A 86-year old patient known to have a serous cystadenoma of the pancreas treated conservatively through a close clinical and radiological follow up which was unattended for 4 years ending up to our emergency department suffering an acute abdomen. Exploratory laparotomy revealed a perforated prepyloric ulcer which was treated accordingly. Patient died some weeks later due to severe medical co morbidities.</p> <p>Conclusion</p> <p>Serous cystic neoplasms of the pancreas carry a realistic risk of malignancy despite the general view that they never become malignant. In our opinion the treatment strategy of serous cystic neoplasms of the pancreas should be aggressive even in cases of remote metastases since prognosis of the disease is satisfactory</p

Coordination Specification for Distributed Optimal System Design Using the Chi Language

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76202/1/AIAA-2002-5410-847.pd

Coordination Specification of the Analytical Target Cascading Process using the Chi Language

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76587/1/AIAA-2002-5637-610.pd

Evaluation of DNA ploidy in relation with established prognostic factors in patients with locally advanced (unresectable) or metastatic pancreatic adenocarcinoma: a retrospective analysis

<p>Abstract</p> <p>Background</p> <p>Most patients with ductal pancreatic adenocarcinoma are diagnosed with locally advanced (unresectable) or metastatic disease. The aim of this study was to evaluate the prognostic significance of DNA ploidy in relation with established clinical and laboratory variables in such patients.</p> <p>Methods</p> <p>Two hundred and twenty six patients were studied retrospectively. Twenty two potential prognostic variables (demographics, clinical parameters, biochemical markers, treatment modality) were examined.</p> <p>Results</p> <p>Mean survival time was 38.41 weeks (95% c.i.: 33.17–43.65), median survival 27.00 weeks (95% c.i.: 23.18–30.82). On multivariate analysis, 10 factors had an independent effect on survival: performance status, local extension of tumor, distant metastases, ploidy score, anemia under epoetin therapy, weight loss, pain, steatorrhoea, CEA, and palliative surgery and chemotherapy. Patients managed with palliative surgery and chemotherapy had 6.7 times lower probability of death in comparison with patients without any treatment. Patients with ploidy score > 3.6 had 5.0 times higher probability of death in comparison with patients with ploidy score < 2.2 and these with ploidy score 2.2–3.6 had 6.3 times higher probability of death in comparison with patients with ploidy score < 2.2.</p> <p>Conclusion</p> <p>According to the significance of the examined factor, survival was improved mainly by the combination of surgery and chemotherapy, and the presence of low DNA ploidy score.</p

A response to industrial maturity and energetic issues: a possible solution based on constructal law

n/

GIST suture-line recurrence at a gastrojejunal anastomosis 8 years after gastrectomy: Can GIST ever be described as truly benign? A case report

We present the case of a 71 year old man with recurrence of a Gastro Intestinal Stromal Tumour (GIST) at the gastrojejunal anastomosis eight years following partial gastrectomy for a very small primary gastric GIST. He presented acutely on both occasions with haemodynamic shock secondary to massive haematemesis. During his initial presentation in 2001, an emergency laparotomy was performed, demonstrating a pre-pyloric ulcerative lesion. The histopathology was in keeping with a diagnosis of a gastric GIST with a &lt; 2 cm tumour, with &lt;5 mitosis per 50/HPF, no signs of necrosis and invasion limited to the mucosa. Eight years later the same patient presented with a similar clinical picture of haemodynamic instability secondary to haematemesis. Emergency endoscopy showed an irregularly shaped elevated lesion on the gastrojejunostomy line suggestive of recurrence. He subsequently underwent completion gastrectomy and the histology revealed a 0.8 cm GIST tumour composed of spindle cells with &lt;5 mitosis per 50/HPF, tumor invasion into the submucosa and positive expression of c-kit and SMA. The patient remains recurrence free 18 months post surgery. The literature suggests that tumour size, mitotic rate and tumour site are the most important predictive factors of recurrence. Additional features such as the presence of necrosis, local tumour invasion and positive resection margins, can also influence recurrence rates. In this case the lesion was a gastric GIST, very small (&lt;2 cm), had low proliferation rate (&lt;5 mitosis/HPF), lacked necrosis and was limited to the mucosa. Recurrence of such a primary GIST at the anastomotic line, eight years after initial resection has never been demonstrated among review of several thousand primary GISTs. This case highlights how even the most innocent GISTs can never be described as truly benign. © 2010 Papalambros et al; licensee BioMed Central Ltd