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Many students, residents, and learners have heard of the infamous bank robber, who when arrested was asked “Why do you rob banks?” He supposedly replied “Because that’s where the money is.” Except it did not happen that way. He did rob close to a hundred banks and jewelry stores and stole an estimated $2,000,000. 1 A well-known maxim in medicine and surgery, few know the details of the unrelated men behind “Sutton’s Law.”

Where medical interventions are licensed based on only uncontrolled study data (for example a single-arm trial), a common approach for estimating the incremental benefit is to compare the treatment to a ‘historical control’; data collected from patients who did not receive the intervention. We illustrate with motivating examples two methods for the creation of historical controls where disease progression and overall survival are typically the key clinically meaningful endpoints. The first method utilises information routinely collected in a clinical trial programme: patients’ time to disease progression on their previous line of treatment against which outcomes can be compared. The second uses published clinical outcomes for the prior line of treatment which can be extrapolated to estimate outcomes at the next line. As examples we use two pharmaceuticals licensed on the basis of uncontrolled clinical studies – idelalisib for double-refractory follicular lymphoma and ofatumumab for double-refractory chronic lymphocytic leukemia. Although subject to limitations that should be considered on a case-by-case basis, the methods may be appropriate when trying to quantify the clinical benefit of treatment based on limited and uncontrolled trial data. As a result, the methods can be used to inform health technology adoption decisions.

With quality and public reporting of increasing importance, benchmarks are anticipated to grow in relevance. We studied cholecystectomy in a practice in an urban tertiary care hospital. A total of 1083 cholecystectomies were performed in 2008 and 2009. Laparoscopic cholecystectomy was performed in 97.8 per cent of patients with a 2.2 per cent conversion rate. A planned open procedure was performed in only 2.2 per cent of patients. Approximately half of procedures were urgent and performed during an acute hospitalization. Most patients (74%) were female and most patients were overweight or obese (64.8%). Ages into the tenth decade of life were represented. Comorbidities included hypertension, 28.7 per cent; coronary disease, 15.6 per cent; diabetes mellitus, 13.4 per cent; gastroesophageal reflux disease, 10.7 per cent; and asthma, 5.5 per cent. Of female patients, 98 (12.2%) were postpartum and five (0.6%) were pregnant. Of 137 patients without gallstones, 59.1 per cent had biliary dyskinesia and 27 per cent had acalculous cholecystitis. Preoperative magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) were performed in most patients with suspected choledocholithiasis. Intraoperative cholangiograms were performed in 6.9 per cent of patients, 3.3 per cent for abnormal liver function studies. Postoperative ERCP was used in most patients with positive intraoperative cholangiograms. All-cause mortality was 0.8 per cent and attributable mortality was 0.2 per cent. Complications occurred in 7.5 per cent of patients, including retained common bile duct stones in 1.1 per cent, bile duct leak in 0.3 per cent, and common bile duct injury in 0.1 per cent.

This paper investigates the feasibility of using zinc sulfide manganese (ZnS:Mn) concentrated vinyl ester resin as a photon emitter for damage monitoring of polymer composites under flexural loading. Unreinforced vinyl ester resins doped with optical emitting materials (ZnS:Mn phosphors) in ratios of 5–50% by weight were cast, and subjected to flexural loading using standard 3-point bend tests. The intent of this work was to observe the transient response of triboluminescence (TL) throughout the failure cycle. Results indicate TL crystals emit light at various intensities corresponding to crystal concentration and imminent matrix fracture. Consequently, concentrated samples showed nearly 50% reductions of mechanical moduli. Scanning electron microscopy (SEM) revealed particulate inclusions with shearing bands and semblance of particle to resin adhesion. Despite significant parasitic effect to mechanical properties, the triboluminescent properties occur at yielding and point of matrix fracture.

Extensive research work has been done in recent times to apply the triboluminescence (TL) phenomenon for damage detection in engineering structures. Of particular note are the various attempts to apply it in the detection of impact damages in composites and aerospace structures. This is because TL-based sensor systems have a great potential for wireless, in-situ and distributed (WID) structural health monitoring when fully developed. This review article highlights development and the current state-of-the-art in the application of TL-based sensor systems. The underlying mechanisms believed to be responsible for triboluminescence, particularly in zinc sulfide manganese, a highly triboluminescent material, are discussed. The challenges militating against the full exploitation and field application of TL sensor systems are also identified. Finally, viable solutions and approaches to address these challenges are enumerated.

Utilization of the virtual classroom as a laboratory for teaching and learning experimentation has increased significantly in recent years as development tools for Web-based applications have become easier to use, and computers have become more capable and less expensive. But, does the virtual classroom improve student learning?Herein we describe the results of two experiments conducted on sections of an Engineering Economy course (ISE 2014) at Virginia Tech during the Spring 2000 and Fall 2000 semesters. The two experiments were designed to determine if student learning of Engineering Economy was significantly affected by two treatments: 1) An industrial team project provided by General Electric (GE) in the Spring and Fall of 2000, and 2) Web-based supplemental course materials in the Fall of 2000. The actual final scores of students in the experimental and control sections were compared (for the Spring and Fall experiments) in order to determine the impact on learning of the project and/or the Web-based...

Traditional manufacturing systems are built on the principle of economies of scale. Here, the large fixed costs of production are depreciation-intensive because of huge capital investments made in high-volume operations. These fixed costs are spread over large production batch sizes in an effort to minimize the total unit costs of owning and operating the manufacturing system. As an alternative to “batch-and-queue,” high-volume, and inflexible operations, the principles of the Toyota Production System (TPS) and lean manufacturing have been widely adopted in recent years in the US [1] , [2] , [3] , [4] . In this paper, we illustrate an equipment replacement decision problem within the context of lean manufacturing implementation. In particular, we demonstrate how the value stream mapping (VSM) suite of tools can be used to map the current state of a production line and design a desired future state. Further, we provide a roadmap for how VSM can provide necessary information for analysis of equipment replacement decision problems encountered in lean manufacturing implementation.

This paper discusses a measure for estimating the wealth creation potential of capital investments in manufacturing. The measure, called “Economic Value Added,” has recently become popular in the United States and can be derived from an after-tax analysis of cash flows generated by a capital investment. A proposed investment in manufacturing capacity is analyzed to illustrate the after-tax cash flow calculations required to determine its EVA potential.

With quality and public reporting of increasing importance, benchmarks are anticipated to grow in relevance. We studied cholecystectomy in a practice in an urban tertiary care hospital. A total of 1083 cholecystectomies were performed in 2008 and 2009. Laparoscopic cholecystectomy was performed in 97.8 per cent of patients with a 2.2 per cent conversion rate. A planned open procedure was performed in only 2.2 per cent of patients. Approximately half of procedures were urgent and performed during an acute hospitalization. Most patients (74%) were female and most patients were overweight or obese (64.8%). Ages into the tenth decade of life were represented. Comorbidities included hypertension, 28.7 per cent; coronary disease, 15.6 per cent; diabetes mellitus, 13.4 per cent; gastroesophageal reflux disease, 10.7 per cent; and asthma, 5.5 per cent. Of female patients, 98 (12.2%) were postpartum and five (0.6%) were pregnant. Of 137 patients without gallstones, 59.1 per cent had biliary dyskinesia and 27 per cent had acalculous cholecystitis. Preoperative magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) were performed in most patients with suspected choledocholithiasis. Intraoperative cholangiograms were performed in 6.9 per cent of patients, 3.3 per cent for abnormal liver function studies. Postoperative ERCP was used in most patients with positive intraoperative cholangiograms. All-cause mortality was 0.8 per cent and attributable mortality was 0.2 per cent. Complications occurred in 7.5 per cent of patients, including retained common bile duct stones in 1.1 per cent, bile duct leak in 0.3 per cent, and common bile duct injury in 0.1 per cent.

This paper describes the use of multimedia lectures in an engineering economy course that is attended by 200 sophomore engineering students at Virginia Tech. The purpose of this paper is to examine the important issue of applying innovative information technology to support the effective dissemination of learning materials and to report on an experiment in which the benefits of multimedia-based support materials are assessed. Our hypothesis is that students exposed to a series of multimedia-based lectures will exhibit greater interest in the subject matter and will eventually perform better or as well as students in the traditional teaching environment. In addition, we hope to establish that students tend to become more involved (participate actively) in a multimedia-based teaching environment to the extent of actually making positive suggestions for improvement to the computer presentations. Just as important, we will support and encourage such contributions made by cross-disciplinary groups of students in the hope of cultivating student's interest in the subject matter throughout the course.

One of the major risks encountered in economic evaluation of foreign direct investment is the changes in future exchange rates that may affect the accuracy of the estimated economic worm of the investment. The objective of this article is to present a model for reducing the uncertainty associated with changes in foreign exchange rates when conducting economic evaluations of foreign direct investments. The model uses the Purchasing Power Parity Theorem and weighted averages for creating a procedural approach in which future changes in exchange rates are considered and included in the calculation of an overall profitability measure.

This paper provides a comprehensive list of relevant books and articles pertaining to the subject area of “engineering design,” with specific focus on the methodology, education, economics, and management aspects of the design discipline. The purpose of this survey of engineering design literature is to provide a compendium of books and articles that may be instrumental in facilitating the process of sharing and disseminating design knowledge

The human nervous system (HNS) provides one of the most advanced examples of how to monitor the structural state of a complex system. In attempts to mimic the HNS, a key component has been the development of the sensory receptor. This paper reports on the development of a triboluminescence (TL)-based sensory receptor that converts mechanical energy from fatigue or impact loads and cracks propagation, into optical signals. This sensor system has potential for wireless, in-situ and distributed sensing (WID). The approach differs from existing fiber optic methods in that it does not require any external light source to function. The optical signal is generated through mechanical excitation of the highly triboluminescent ZnS:Mn. It is then transmitted through optical fibers to photomultiplier tubes (PMT) for detecting, quantifying and locating (with further analysis), intrinsic damage in critical engineering structures like concrete bridges. The TL sensory receptor consists of a sensitized portion of a polymer optical fiber (POF) coated with epoxy containing ZnS:Mn crystals. The sensory receptors were then incorporated into cementitious and polymer samples. Results from preliminary investigation showed that the TL sensory receptor gives repeatable responses under multiple impact loads. The triboluminescent intensity of the signal is directly related to the magnitude of the impact load. Results from dynamic mechanical analysis show a reduction in the Tg of the ITOF coating (TSR) with higher concentration of the triboluminescent (ZnS:Mn) crystals for the epoxy system used. There was however significant enhancement of the modulus with increase in the TL crystals. High-performance epoxy system with the principles of particulate composites would be applied in subsequent work to optimize the properties and performance of the TL sensor system.

This paper applies a multi-attribute evaluation model to the choice between local area network (LAN) topologies in an office automation project. A computerized decision support system, JustLAN, has been developed to facilitate sensitivity studies. It incorporates the following features: (1) a group-participative process for data acquisition, (2) the development of ratio-scaled importance weights for the attributes, (3) detailed cost estimation worksheets for the determination of life-cycle costs for feasible alternatives, (4) a graphical assessment of tradeoffs between monetary and nonmonetary considerations, and (5) the capability to conduct on-line sensitivity analyses to test the “robustness” of the recommended alternative to estimation errors. In a sample application of the procedure, involving a LAN selection problem in a government office building, an inferior alternative would have been selected if results of traditional present worth analysis had been followed. Only through the use of multi-attrib...

This paper discusses a fundamental change that appears to be occurring in the practical and theoretical aspects of engineering economy. Recent emphasis on the engineer's role in strategic and design-related decision processes has created a very real need for a change in focus in engineering economy technique and methodology. Several areas of research opportunity that arise because of the paradigm shift are also identified herein.

Most traditional approaches to capital expenditure analysis have been partially successful in explicitly accounting for risk. A utilitarian model for risk treatment is described in this paper. Specifically, we address two major aspects of the utilitarian approach: (1) the mathematical legitimacy of the underlying utility function with respect to its domain of economic significance and (2) the way “Expectancy-Variance” and “Expectancy-Semivariance” compare as risk/return trade-off criteria. In particular, we have shown how commonly used quadratic utility functions present some theoretical and practical inconveniences from an economic standpoint. Then, a hybrid utility function is introduced as a more legitimate and often more realistic model where semi-variance, rather than variance, is used as a measure of the investment riskiness.

Many universities are rushing to be active participants or leaders in online instruction. The effectiveness of materials and the time and effort for the initial development of web-based course materials are significant factors affecting the success of these efforts. Recently, a variety of software tools have emerged to meet the demand for the development and maintenance of web-based course materials. Tools are varied in terms of ease of use, skills needed, time requirements, course support features, initial costs, and licensing fees for users. This paper provides a brief overview of several tools for web-based educational needs. A summary of features, strengths, and limitations is provided Clarity of information for Internet users will be emphasized, including factors and display problems to keep in mind during design and development of online materials. An example based on an existing "virtual" classroom for the economics of engineering design is included to reinforce discussion of layout, development, and presentation of materials.

The objective of this project was to conduct and report on experiments to determine whether industrial case studies, web-based course materials, and communication enhanced by the Internet can improve the proficiency of student learning in engineering economy.

Necrotizing fasciitis is a highly morbid soft tissue infection that rarely involves the upper torso. An extremely unusual case of necrotizing fasciitis of the chest wall is reported, including the method by which an open thoracic cage was managed. This represents the second reported case of a patient surviving necrotizing fasciitis of the chest wall requiring rib resection and chest wall reconstruction.

The world-wide competitive economy is forcing us to utilize fully the best equipment and techniques available with efficient control of organizational structure to produce high quality, well-designed products at lower prices and in less time. Increasing awareness is being directed to the product design phase, because the more advanced CIM technologies are of little consequence unless the product design lends itself to the overall system utilizing all available and relevant technologies. For instance, the following statements represent the significance of product design.

The decision to invest in capital equipment is one of the most critical decisions an executive can make. A prudent capital investment in machinery and advanced technologies will increase production, reduce costs, and provide a competitive advantage. The future health of the company is closely tied to the investment decision.

The minimum revenue requirements method of capital investment analysis is widely used by investor-owned utilities. The present worth method is more familiar to graduates of industrial engineering curricula. This paper considers a particular variant of the minimum revenue requirements method and presents the assumptions that must be adopted to insure exact equivalence between the two methods. A numerical example is provided to illustrate the tabular computation algorithm commonly used by practitioners of both methods. Several models for computing revenue requirements are given, each based on a different view of the cost of capital. The results of these computations are compared to those obtained when the present worth method is used to treat borrowed funds both implicitly and explicitly. Theorems from Oso [13] are used to generalize the results. Additional theorems extend findings regarding the equivalence of the minimum revenue requirements and the present worth methods.

This case study is an evaluation of actual alternatives for capacity expansion of an electrical power company. A systematic analysis of the important parameters of this complex problem is described to illustrate how multiple attribute decision analysis can be utilized to include the monetary and nonmonetary aspects of such a real world capacity expansion problem. The service cost data utilized is the type generated routinely by utilities and/or regulatory staffs. However, the use of outage costs and socio-economic coats demonstrates that the readily available service coats data can be expanded and combined into a framework that allows a more detailed analysis of the complex, capacity planning problem. The information reported here has been altered to the extent necessary to conceal the identity of the utility.

The association of thunderstorm occurrence in Alaska with low-level convergence is studied. The results indicate that the main contributing factor to thunderstorm development is the low-level convergence produced by the trough or Low pressure center that persists over Alaska during much of the summer.

A model is developed for predicting workload requirements for scheduled health care services. The model is then applied to an actual planning problem for a radiology department. The probability distribution of future workload is represented by the convolution of two families of random variables such that a compound Poisson process adequately describes workload requirements. The model developed herein can be applied to a wide assortment of capacity-expansion problems that are characterized by discrete demands (e.g. number of jobs) occurring in a given period of time, where the amount of time needed to complete each job is a continuous random variable.

1. 1. Experience with thirty-five patients with popliteal vessel injury is presented. 2. 2. Failure to perform primary vein repair resulted in venous insufficiency and severe morbidity in four patients. 3. 3. Massive edema did not occur in any of twenty-one patients who had primary vein repair. Early venograms showed a patent vein repair in eight of eleven patients. 4. 4. We believe that the data presented demonstrate the importance and feasibility of popliteal vein repair.

(1983). Review of: “ INFLATION IN ENGINEERING ECONOMIC ANALYSIS”by Byron W. Jones, John Wiley & Sons, New York, 1982, 216 pages. The Engineering Economist: Vol. 28, No. 4, pp. 339-339.