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891.
Professional software engineering continues to face problems that involve large-scale (complex) software systems development. Such efforts typically require team collaboration over months, possibly years. Once implemented, the system must be maintained for sometimes decades. This development and maintenance life cycle requires not only technical knowledge and skills in software development, but also the knowledge and skills associated with software process. We believe the traditional computer science curriculum fails to consider this spectrum of needs. We also believe, however, that software engineering must use certain elements of the core knowledge and skills taught by computer scientists as its foundation. We describe lessons learned from the 10-year collaboration between Monmouth University and the Software Engineering Center of the US Army's CECOM (Communications Electronics Command). The center recruits electrical engineering and computer science graduates from academic institutions in the geographic regions surrounding its various installations to be part of its intern program; Monmouth University, in turn, incorporates the demands of the intern program in its Master of Science in software engineering curriculum 相似文献
892.
893.
The authors report the case of a woman admitted to hospital for minor trauma of the left hip and who presented major ST segment elevation on the second day suggesting an acute anterior wall myocardial infarction at the same time as a cerebrovascular accident. Complementary investigations and follow-up excluded the diagnosis of myocardial infarction with normalisation of the ECG on the 5th day. ECG changes during cerebrovascular accidents may be very variable ranging from extrasystoles to ST elevation mimicking myocardial infarction. They carry a poor prognosis with an increased risk of sudden death necessitating continuous ECG monitoring until the ECG reverts to normal. The cardiac involvement is not ischaemic but due to disease of the insular cortex of the brain which induces myocytolysis (centered around the intra-cardiac nerve endings) due to the sudden liberation of catecholamines. These lesions may be treated by propranolol or phentolamine. 相似文献
894.
895.
The Effect on the subgingival microflora of a single topical administration of a 95% collagen and 5% metronidazole device in combination with debridement was investigated in 30 adult periodontitis patients in comparison with mechanical treatment alone. For each patient, plaque samples from test and control sites in cuspids and bicuspids were collected for culture and enumeration of total anaerobically cultivable bacteria (TA), black-pigmented anaerobes (BPA), and Actinobacillus actinomycetemcomitans (Aa). Spirochetes and fusiforms were quantified by direct microscopic examination after Giemsa staining. A decrease was observed for all parameters, and a significant difference in comparison with the control group was found for fusiforms. After treatment, a lower number of Aa positive sites were observed in the test group (13/25). These results show that a single application of topical metronidazole seems to be effective as adjunctive antimicrobial treatment in adult periodontitis. 相似文献
896.
OBJECTIVE: To investigate if unexpected behaviour of neonatal and paediatric patients connected to syringe pumps could be explained by transient elevation of these devices. DESIGN: Five different commercially available syringe-pumps were set at an infusion rate of 1 ml/h and then subjected to a vertical displacement manoeuvre (height 1 m). The actual delivered infusion volumes in association with the displacement manoeuvre were measured by a high precision weight scale connected to a computer. SETTING: A medical technology laboratory in a university hospital. MEASUREMENTS AND RESULTS: Elevation of the devices resulted in a rapid bolus injection of 0.19-2.28 ml. Returning the devices to their original positions resulted in an aspiration into the system of 0.06-0.34 ml. The times both for bolus injection and for aspiration into the system were less than 1 min in all cases. The updown manoeuvre was followed by a period with zero infusion ranging from 8 to 105 min. CONCLUSIONS: Design flaws in the construction of syringe pumps can expose patients to substantial danger following vertical displacement if potent drugs are being infused. If potent drugs are infused, care should be taken not to change the vertical position of the syringe pump even for short periods of time. Before buying new equipment, the authors recommend that the delivery characteristics of these devices should not only be tested during ordinary bench testing but should also include the reaction to a vertical displacement manoeuvre. 相似文献
897.
Algorithm for cosine transform of Toeplitz matrices 总被引:1,自引:0,他引:1
An algorithm for calculating the 2D cosine transform of a Toeplitz matrix is presented. The algorithm is based on the application of 1D cosine transforms. More specifically, four 1D cosine transforms of size N are needed to obtain the transform of a Toeplitz matrix of size N×N. This is an improvement over previously published algorithms. The algorithm is also simple and regular 相似文献
898.
A generator of chaos in wavelength is reported. It is formed by a wavelength-tunable laser diode with a time delayed feedback loop in which a wavelength nonlinear-linear device is introduced. The dynamical regime of wavelength emission thus obtained is ruled by a differential difference equation. Experimental results are compared with numerical simulations and with previous theoretical and experimental results 相似文献
899.
A method based on use of Hardin's homogeneous model is proposed for calculation of the deformation modulus of noncohesive
soils. Completely satisfactory correspondence between computed and experimental values of the deformation modulus of sands
is demonstrated.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 2–5, July–August, 1994. 相似文献
900.
The use of conventional ultrasound systems to image the upper airway has been limited because ultrasound energy is attenuated by the air column. In an attempt to study upper airway geometry, we developed a computer controlled bi-directional ultrasound system which combines two conventional ultrasound devices with computer image processing to yield images of upper airway structures. Human studies and cadaver studies were performed to evaluate the system. Images acquired by the bi-directional ultrasound system were comparable to images from 3D volume rendered CT scans. This system may provide valuable data in the study of upper airway physiology and pathology. 相似文献