177,636 research outputs found
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
The Use of Glyburide Compared With Other Sulfonylureas and the Risk of Cancer in Patients With Type 2 Diabetes
No full textObjective: To determine whether the use of glyburide is associated with an increased risk of cancer compared with the use of other second-generation sulfonylureas among patients with type 2 diabetes.
Research design and methods: The U.K. Clinical Practice Research Datalink was used to conduct a cohort study among 52,600 patients newly prescribed glyburide or other second-generation sulfonylureas between 1 January 1988 and 31 July 2013. A time-dependent Cox proportional hazards model was used to estimate adjusted hazard ratios (HRs) and 95% CIs of any cancer associated with the use of glyburide compared with the use of second-generation sulfonylureas. Secondary analyses were conducted to determine whether the association varied with cumulative duration of use and cumulative dose (expressed as defined daily dose [DDD]).
Results: During 280,288 person-years of follow-up, 4,105 patients were given a new diagnosis of cancer (incidence rate 14.6 per 1,000 person-years). Overall, when compared with the use of other second-generation sulfonylureas, the use of glyburide was associated with a nonsignificant increased risk of any cancer (HR 1.09 [95% CI 0.98-1.22]). In secondary analyses, duration- and dose-response relationships were observed, with longer cumulative durations and cumulative doses associated with an increased risk of any cancer (>36 months: HR 1.21 [95% CI: 1.03-1.42]; >1,096 DDDs: HR 1.27 [95% CI 1.06-1.51]).
Conclusions: In this population-based cohort study, longer cumulative durations and higher cumulative doses of glyburide were associated with an increased risk of cancer
Intern experience at CH���M Hill, Inc.: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical referencesA review of the author's internship experience with CH���M HILL, Inc.
during the period September 1975 through May 1976 is presented. During this nine month
internship the author worked as an Engineer II in the Industrial Processes discipline of this
large consulting engineering firm... The author's prime responsibility was as one of three
lead design engineers on the design of a large wastewater treatment facility for a pulp mill
in Hoquiam, Washington owned by ITT Rayonier Inc. The work generally consisted of the design
of individual treatment units and associated piping and pumping. The purpose of the project
was to provide wastewater treatment capabilities that would satisfy the effluent limitations
(standards) imposed upon the mill by the State of Washington Department of Ecology and the
U.S. Environmental Protection Agency. The author's assignment also entailed necessary
interaction with the project manager and other CH���M HILL design engineers and support staff
members, the client's representatives, and representatives of two other consulting engineering
firms working on the project. Thus, the internship position at CH���M HILL provided considerable
experience coordinating the author's work with the work of other engineers, guiding the design
and administrative efforts of a support staff, and interacting regularly with the client and
other consulting firms. This broad exposure to a variety of engineering and organizational
problems provided a valuable educational experience
Social Influence Given (Partially) Deliberate Matching: Career Imprints in the Creation of Academic Entrepreneurs
No full textActors often match with associates on a small set of dimensions that matter most for the particular relationship at hand. In so doing, they are exposed to unanticipated social influences because counterparts have more interests, attitudes, and preferences than would-be associates considered when they first chose to pair. This implies that some apparent social influences (those tied to the rationales for forming the relationship) are endogenous to the matching process, while others (those that are incidental to the formation of the relationship) may be conditionally exogenous, thus enabling causal estimation of peer effects. We illustrate this idea in a new dataset tracking the training and professional activities of academic biomedical scientists. In qualitative and quantitative analyses, we show that scientists match to their postdoctoral mentors based on two dominant factors, geography and scientific focus. They then adopt their advisers' orientations toward commercial science as evidenced by the transmission of patenting behavior, but they do not match on this dimension. We demonstrate this in two-stage models that adjust for the endogeneity of the matching process, using a modification of propensity score estimation and a sample selection correction with valid exclusion restrictions. Furthermore, we draw on qualitative accounts of the matching process recorded in oral histories of the career choices of the scientists in our data. All three methods-qualitative description, propensity score estimators, and those that tackle selection on unobservable factors-are potential approaches to establishing evidence of social influence in partially endogenous networks, and they may be especially persuasive in combination.
Intern experience at the Texas Transportation Institute: an internship report
No full text"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirements for the degree of Doctor of Engineering."Includes vita (leaf 91)Includes bibliographical references (leaf 57)This report discusses the author's engineering experience at the Texas
Transportation Institute (TTI), Texas A&M University from March 1974 through July 1977. A
report of this experience plus twelve additional hours of academic course work were
substituted for an internship according to requirements established by the College of
Engineering. Although the author could not retroactively establish objectives of the type
associated with a typical internship, the work experience gained could be related to the two
general objectives of an intership: 1. To demonstrate an identifiable contribution to the
organization in which the intern served, and 2. To enable the intern to become aware of the
non-technical aspects of working as an engineer in a non-academic environment. While a member
of the Texas Transportation Institute staff, the author worked on a number of projects in the
areas of highway traffic engineering research and the preparation of continuing education
courses for transportation engineering officials. These assignments were contained within the
Urban Transportation Systems Division of TTI. This report delineates the author's contribution
to four particular projects and discusses the technical as well as non-technical experience
gained from each. Having been exposed to more engineering situations than many of the other
Doctor of Engineering students, the author has already formulated some rather specific
milestones for the future. The Doctor of Engineering program is discussed in conjunction with
its potential for helping the author attain these career goals and objectives. Also, some
thoughts are presented regarding the Doctor of Engineering as a viable alternative to the
Ph.D. in preparing for a career in engineering higher education
The long-wavelength view of GG Tau A: rocks in the ring world
No full textWe present the first detection of GG Tau A at centimetre wavelengths, made with the Arcminute Microkelvin Imager Large Array at a frequency of 16 GHz (λ = 1.8 cm). The source is detected at >6 σrms with an integrated flux density of S16GHz = 249 ± 45 µJy. We use these new centimetre-wave data, in conjunction with additional measurements compiled from the literature, to investigate the long-wavelength tail of the dust emission from this unusual protoplanetary system. We use an MCMC-based method to determine maximum likelihood parameters for a simple parametric spectral model and consider the opacity and mass of the dust contributing to the microwave emission. We derive a dust mass of Md ~ 0.1 Msun, constrain the dimensions of the emitting region and find that the opacity index at λ > 7 mm is less than unity, implying a contribution to the dust population from grains exceeding ~4 cm in size. We suggest that this indicates coagulation within the GG Tau A system has proceeded to the point where dust grains have grown to the size of small rocks with dimensions of a few centimetres. Considering the relatively young age of the GG Tau association in combination with the low derived disc mass, we suggest that this system may provide a useful test case for rapid core accretion planet formation models
Hepatic resection for hepatocellular carcinoma in patients with Child–Pugh's A cirrhosis: is clinical evidence of portal hypertension a contraindication?
No full textAbstractBackgroundAccording to international guidelines [European Association for the Study of the Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD)], portal hypertension (PHTN) is considered a contraindication for liver resection for hepatocellular carcinoma (HCC), and patients should be referred for other treatments. However, this statement remains controversial. The aim of this study was to elucidate surgical outcomes of minor hepatectomies in patients with PHTN (defined by the presence of esophageal varices or a platelet count of <100 000 in association with splenomegaly) and well‐compensated liver disease.MethodsBetween 1997 and 2012, a total of 223 cirrhotic patients [stage A according to the Barcelona Clinic Liver Cancer (BCLC) classification] were eligible for this analysis and were divided into two groups according to the presence (n = 63) or absence (n = 160) of PHTN. The demographic data were comparable in the two patient groups.ResultsOperative mortality was not different (only one patient died in the PHTN group). However, patients with PHTN had higher liver‐related morbidity (29% versus 14%; P = 0.009), without differences in hospital stay (8.8 versus 9.8 days, respectively). The PHTN group showed a worse survival rate only if biochemical signs of liver decompensation existed. Multivariate analysis identified albumin levels as an independent predictive factor for survival.ConclusionsPHTN should not be considered an absolute contraindication to a hepatectomy in cirrhotic patients. Patients with PHTN have short‐ and long‐term results similar to patients with normal portal pressure. A limited hepatic resection for early‐stage tumours is an option for Child–Pugh class A5 patients with PHTN
Intern experience at Honeywell, Inc., Large Information Systems Division: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical references (leaves 169-173)This report describes the author's internship assignment at Honeywell
Inc. - Large Information Systems Division from January, 1982 through August, 1982. The purpose
of the assignment was to fulfill the internship requirements of the Doctor of Engineering
Program. During the internship, the author held the position of VLSI design engineer, where he
worked on a predefined project. The project's objective was to evaluate how circuit designs
based on an advanced CMOS process, can be applied to hardware products at LISD. The internship
allowed the author to successfully apply the MOS circuit design training, which ws developed
at Texas A&M, to an industrial project. In addition, involvement in different activities
and exposure to the various problems not encountered in academia, made this internship an
invaluable experience
\u27Letters Full of Love\u27: Wayne Booth\u27s Theories of the Implied Author and Reader in Brad Marsh\u27s WWII Correspondence
No full textThis project consists of a qualitative study of the WWII correspondence of Captain Brad Marsh from the collection of letters donated by his daughter on April 26, 2013. I draw from the narrative theory and works of Wayne Booth to examine Marsh’s construction of self as an implied author by examining how he presents his experiences and portrays his emotions. I also examine how Marsh constructs his implied self by paying attention to details such as the information he shares with Lynn and how he presents it. I explore the nature of the implied author and reader in the correspondence and also how the relationship between the implied writer and reader influences the understanding of an unintended audience
Intern Experience at MEL, Inc.: An Internship Report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical references (leaves 82-85)...The author spent a one-year internship at MEL, Inc., a civil and
mechanical engineering consulting firm located in Baton Rouge, Louisiana. By special
arrangement with the president of the firm, the author was able to participate in roles at
various levels within the firm. These activities included engineering design, supervision and
management, project cost control, and interface with top level management. During this period,
the author has been engaged in the following assignments: 1. Serving as senior project
engineer on the Louisiana Training Institution air conditioning and heating project, 2.
Serving at the review and advisory level for three projects, 3. Studying and implementing
computer aided design and drafting system for MEL, Inc. 4. Developing a projet cost control
system that is interactive with the firm's payroll program. 5. Upgrading the firm's computer
capacity. 6. Performing special assignments from the President, Executive Vice-President,
Manager of Operation and Manager of Business and Fiscal Affairs at MEL, Inc. These activities
involved the application of scientific principles to the design, installation, and improvement
of integrated systems of people, materials, and equipment to provide the most effective
operating and work procedures. As a result of this involvement in a wide range of assignments,
the author now has a broadly based experience in a consulting engineering firm as both
engineer and manager. The author also found that well-developed, practical courses in
communication, business, engineering, law, and management from the Doctor of Engineering
program at Texas A&M University contributed greatly to this successful internship with
MEL, Incorporated
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