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Development of Light Weight Structures to Provide Blast-Resistant Designs

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Transactions of Tianjin University 2006年第B9期12卷 16-21页

作者： crawford john e Karagozian & Case 2550 N.Hollywood Way #500BurbankCA 91505USA

In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMeD steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.

关键词： blast containment package handling facility hardened design light weight structures COLD-FORMeD steel structures

Development of Shallow Footing Anti-Ram Bollard System Through Modeling and Testing

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Transactions of Tianjin University 2006年第B9期12卷 46-50页

作者： crawford john e Karogozian & Case 2550 N.Hollywood WaySuite 500BurbankCA 91505USA

In past terrorist attacks, vehicle borne improvised explosive devices (VBIeD) have been the primary manner of attacking buildings and infrastructures. Preventing unauthorized vehicles from approaching a protected area with anti-ram systems would maintain an established standoff distance against moving and stationary vehicles and consequently reduce blast and debris threats. This strategy has been considered the first line of defence against terrorists. Several types of anti-ram devices have been developed in accordance with U. S. Department of State K-rating criteria, for example, wedge barriers, rising beams, sliding/swing gates, and drop arms. However, these devices typically need a deep foundation for installation and can't be implemented into many locations where a depth of excavation is limited in order to protect utility lines of buildings and infrastructures. This paper presents a recent development of a series of shallow footing anti-ram bollard systems (SFABS) that can satisfy K-12 rating with only five-inch thick footing. A high-fidelity physics based finite element technique with a vehicle crash model is used for predicting anti-ram capacity and determining design parameters of the SFABS. Full-scale vehicle crash tests of the developed SFABS systems have been carried out to validate the design and analysis.

关键词： anti-ram bollard shallow footing crash testing finite element analysis

Fo screen or not to screen： the prostate cancer dilemma

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Asian Journal of Andrology 2015年第1期17卷 44-45页

作者： Nelson N Stone e David crawford Departments of Urology and Radiation Oncology The Icahn School of Medicine at Mount Sinai New York NY USA Department of Surgery Division of Urology and Radiation Oncology The Anschutz Cancer Center The University of Colorado Health Sciences Center. Aurora. CO. USA.

The european Randomized Study of Screening for Prostate （eRSPC） has updated their previous seminal report on prostate cancer mortality comparing screened men to controls. Now with 13 years follow-up, the rate ratio of prostate cancer mortality was 0.79 favoring the screened population. The authors concluded that there was a ＂substantial reduction in prostate cancer mortality attributable to testing with prostate-specific antigen （PSA）＂ but they also stated that a＂quantification of harms＂ needed to be addressed. The issue of harms was not addressed by the eRSPC （at least not in this report） and hence this additional statement most likely reflects the controversy currently surrounding the risks associated with over-diagnosis and treatment of indolent diseases inadvertently detected by a screening protocol, In addition, the positive results from this trial conflict with those of the prostate, lung, colorectal and ovarian （PLCO）2 study and reouire further elaboration.

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Prostate-specific antigen （PSA） screening： has the pendulum swung too far？

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Asian Journal of Andrology 2011年第5期13卷 655-656页

作者： Jason M Phillips e David crawford Department of Urology University of Colorado HealthSciences Center Aurora CO 80045 USA

Prostate-specific antigen （PSA） along with digital rectal exam has been the standard for prostate cancer screening in the United States for the past 20 years.1 During this time period, the improved detection of prostate cancer decreased related mortality more than 30%.2 In fact, metastases and their comorbidities have decreased more than 75% since the early 1990s, resulting in a higher incidence of early organ-confined disease. While it is clear that prostate cancer mortality statistics have improved, it is unclear whether men are overscreened.

关键词： overscreened Prostate-specific

Search for a natural scientific measure of economy

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Frontiers of environmental Science & engineering 2011年第1期5卷 111-118页

作者： john e COULTeR Xiwangzhuang Shuangqing RdHaidianBeijing 100084China

Through human history,wealth has been measured in grain,gold,and,now,*** counterfeiting of coins and notes goes back a long way,it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our earth and *** schemes using analysis of utility functions,oil equivalents,entropy,energy,and other units have been tried and,while helping to understand some basic processes and flows,have always been swamped by the machinations of financiers and the attention big sums of money ***,the concept of exergy,pioneered in eastern europe in the 1950s,is being researched,developed,and applied,especially in China,driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises.A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not *** that understanding,any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.

关键词： climate change financial crisis energy exergy environment

SWITCHING AND SeQUeNCING AVAILABLe THeRAPIeS SO AS TO MAXIMIZe A PATIeNT＇S eXPeCTeD TOTAL LIFeTIMe

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International Journal of Biomathematics 2012年第4期5卷 113-125页

作者： john e. GOULIONIS Department of Statistics and Insurance Science University of Piraeus 80 Karaoli a Dimitriou Street 18534 Piraeus Greece

This paper has focused on applying mathematical techniques to address fundamental question in therapy planning when to switch, and how to sequence therapies. We consider switching and sequencing available therapies so as to maximize a patient＇s expected total lifetime. We assume knowledge only about the lifetime distributions induced by the therapies. We discuss a specialization of this model that is tailored to a frequently reoccurring type of management problem, where our goal is to determine the best timing for testing and treatment decisions for patients with ischemic heart disease. Typically, decisions are made with an overall, goal of maximizing the patient＇s expected lifetime or quality-adjusted lifetime.

关键词： expected total lifetime maintenance ischemic heart disease stochasticordering relationships statistical distributions.

Redox therapeutics in hepatic ischemia reperfusion injury

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World Journal of Hepatology 2014年第1期6卷 1-8页

作者： Rakesh P Patel john D Lang Alvin B Smith Jack H crawford Department of Pathology Center for Free Radical Biology University of Alabama at Birmingham Department of Anesthesiology and Pain Medicine University of Washington School of Medicine Department of Anesthesiology University of Alabama Birmingham Division of Cardiothoracic Anesthesia Department of Anesthesiology University of Alabama Birmingham

Ischemia-reperfusion plays a major role in the injury experienced by the liver during transplantation. Much work has been done recently investigating the role of redox species in hepatic ischemia-reperfusion. As animal models are better characterized and developed, and more insights are gained into the pathophysiology of hepatic ischemia reperfusion injury in humans the questions into exactly how oxidants participate in this injury are becoming more refined. These questions include effects of cellular location, timing of injury, and ability of therapeutics to access this site are increasing our appreciation of the complexity of ischemia reperfusion and improving attempts to ameliorate its effects. In this review, we aim to discuss the various methods to alter redox chemistry during ischemia reperfusion injury and future prospects for preventing organ injury during hepatic ischemia reperfusion.

关键词： Ischemia Reperfusion Pre-conditioning Nitrite

Multi-length scale modeling of carburization,martensitic microstructure evolution and fatigue properties of steel gears

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Journal of Materials Science & Technology 2020年第14期47卷 157-165页

作者： edward Charles Henry crawford O’Brien Hemantha Kumar Yeddu School of engineering Newcastle UniversityNewcastle upon TyneNE17RUUnited Kingdom

Multi-length scale modeling is performed to(i)predict the carburized case depth of SAe8620 steel gears by solving the Fick’s second law of diffusion,(ii)model the martensitic microstructure evolution in a grain inside the carburized case as well as to study the effect of stress cycling on retained austenite(RA)and martensite using a 3D phase-field model,(iii)simulate the effect of carburization and different RA contents on macroscale fatigue behavior of SAe8620 steel spur gear using the finite element *** diffusion model predicts that the case depth increases with increasing heat treatment time and *** phase-field simulations show that RA can transform to martensite during fatigue loading,where the extent of the transformation will depend on the type of stresses applied,*** in a high stress regime or low stress regime of fatigue *** transformation of martensite to austenite is also observed in low RA sample under high stress *** macroscale simulations show that the carburized case with high RA gives rise to better fatigue life compared to that with low RA.

关键词： Phase-field model Martensitic transformation Microstructure Gear steel Carburization

New technologies in the gastrointestinal clinic and research: Impedance and high-resolution manometry

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World Journal of Gastroenterology 2009年第2期15卷 131-138页

作者： john e Pandolfino Peter J Kahrilas Division of Gastroenterology Department of Medicine Northwestern University Feinberg School of Medicine Suite 1400 Chicago Illinois 60611 United States

The last five years have been an exciting time in the study of esophageal motor disorders due to the recent advances in esophageal function testing. New technologies have emerged, such as intraluminal impedance, while conventional techniques, such as manometry, have enjoyed many improvements due to advances in transducer technology, computerization and graphic data presentation. While these techniques provide more detailed information regarding esophageal function, our understanding of whether they can improve our ability to diagnose and treat patients more effectively is evolving. These techniques are also excellent research tools and they have added substantially to our understanding of esophageal motor function in dysphagia. This review describes the potential benefits that these new technologies may have over conventional techniques for the evaluation of dysphagia.

关键词： Dysphagia, Multichannel intraluminal Impedance Bolus transit High-resolution manometry esophagogastric junction Achalasia