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1.
Spontaneous resolution of deformities after excision of facial skin lesions has been known and used for a long time by plastic surgeons. The resorption mechanism of deformity is based on natural skin expansion, and seems to be directly related to the action of the muscles of facial expression and their skin relations. Natural expansion has been shown to be effective in children. Between 1990 and 1994 excision of skin lesions, including congenital nevi, leading to postoperative deformity of the cheek, labial commissure, nose, eyelid and forehead, was performed on 35 patients, aged from 3 month to 12 years. The average follow-up is 24 months. For 26 patients (74%), natural resorption was observed 4 or 6 weeks later with good aesthetic results. For 6 patients (17%), the deformity persisted 3 or 6 months later, but did not require any further surgery. For 3 patients (9%), a second operation was necessary. Using the skins natural capacity for expansion in the treatment of facial skin defects in children is a method of reconstruction which has already been used for excision in enforced position. The platysma and muscles of facial expression by their action on skin mobilisation, allow natural expansion. A better knowledge of cutaneous biomechanical properties enables plastic surgeons to find an alternative to other classical methods. 相似文献
2.
Off-Site Exposure to Respirable Aerosols Produced during the Disk-Incorporation of Class B Biosolids
Swee Yang Low Tania Paez-Rubio Carolina Baertsch Matthew Kucharski Jordan Peccia 《Canadian Metallurgical Quarterly》2007,133(10):987-994
Field experiments were conducted at a Class B biosolids land application site in central Arizona to measure, model, and source-track the off-site transport of aerosols emitted when biosolids were disk-incorporated into soils. Real-time PM10 monitoring provided time-resolved aerosol information sufficient for verifying both off-site concentration and off-site exposure time model results. Under the conditions considered and at a distance of 165?m from the aerosol source, biosolids disk-incorporation resulted in an intermittent exposure to biosolids-derived aerosol concentration between 15 and 40?μg/m3 and an inhalable biosolids dose between 2 and 8?μg. Transport modeling predicted that these doses will decrease with increasing wind speed. In addition, three DNA sequence-based biosolids source tracking methods were applied to aerosol samples and confirmed the presence of biosolids in aerosols at 5, 65, and 165?m from the aerosol source. Field measurements and modeling indicate that the nature of biosolids-derived aerosol exposure is a series of intermittent high concentration puffs, rather than a continuous low concentration. 相似文献
3.
A new spreadsheet-cell-object-oriented algorithm for the first-order reliability method is proposed and illustrated for cases with correlated nonnormals and explicit and implicit performance functions. The new approach differs from the writers earlier algorithm by obviating the need for computations of equivalent normal means and equivalent normal standard deviations. It obtains the solution faster and is more efficient, robust, and succinct. Other advantages include ease of initialization prior to constrained optimization, ease of randomization of initial values for checking robustness, and fewer required optimization constraints during spreadsheet-automated search for the design point. Two cases with implicit performance functions, namely an asymmetrically loaded beam on Winkler medium and a strut with complex supports are analyzed using the new approach and discussed. Comparisons are also made between the proposed approach and that based on Rosenblatt transformation. 相似文献
4.
Chor Ping Low 《Communications Letters, IEEE》2005,9(11):1012-1014
One of the main issues to be addressed in topological design of centralized networks is that of assigning terminals to concentrators in such a way that each terminal is assigned to one (and only one) concentrator and the total number of terminals assigned to any concentrator (which is referred to as load in this paper) does not overload that concentrator, i.e. is within the concentrator's capacity. Under these constraints, an assignment with the lowest possible cost is sought. An assignment of terminals to concentrators which minimizes the maximum load among the concentrators (which qualitatively represents congestion at some hot spots in a network service area) is referred to as a min-max load assignment. In this paper, we consider the problem of finding a min-max load assignment with the-lowest cost. We call this problem the Minimum Cost Min-Max Load Terminal Assignment Problem (MCMLTAP). We present an algorithm for MCMLTAP and prove that the problem is optimally solvable in polynomial time using our proposed algorithm. 相似文献
5.
Gang Chen Zhonghua Yang Chor Ping Low 《Industrial Informatics, IEEE Transactions on》2006,2(4):269-280
In this paper, we address agent coordination from a dynamic systems perspective and propose a dynamic coordination model, which is inspired by biological metabolic systems. A new coordination mechanism through dynamic local adjustment (CDLA) is presented, and coordination is achieved when every agent utilizes explicitly the global system dynamics and performs iteratively a dynamic local adjustment procedure. The CDLA mechanism is investigated in an example multiagent shop floor system. The results show that the example manufacturing process is well-coordinated and the coordination approach is practically applicable and effective 相似文献
6.
Integrating heterogeneous distributed COTS discrete-event simulation packages: an emerging standards-based approach 总被引:2,自引:0,他引:2
Taylor S.J.E. Xiaoguang Wang Turner S.J. Low M.Y.H. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2006,36(1):109-122
This paper reports on the progress made toward the emergence of standards to support the integration of heterogeneous discrete-event simulations (DESs) created in specialist support tools called commercial-off-the-shelf (COTS) discrete-event simulation packages (CSPs). The general standard for heterogeneous integration in this area has been developed from research in distributed simulation and is the IEEE 1516 standard The High Level Architecture (HLA). However, the specific needs of heterogeneous CSP integration require that the HLA is augmented by additional complementary standards. These are the suite of CSP interoperability (CSPI) standards being developed under the Simulation Interoperability Standards Organization (SISO-http://www.sisostds.org) by the CSPI Product Development Group (CSPI-PDG). The suite consists of several interoperability reference models (IRMs) that outline different integration needs of CSPI, interoperability frameworks (IFs) that define the HLA-based solution to each IRM, appropriate data exchange representations to specify the data exchanged in an IF, and benchmarks termed CSP emulators (CSPEs). This paper contributes to the development of the Type I IF that is intended to represent the HLA-based solution to the problem outlined by the Type I IRM (asynchronous entity passing) by developing the entity transfer specification (ETS) data exchange representation. The use of the ETS in an illustrative case study implemented using a prototype CSPE is shown. This case study also allows us to highlight the importance of event granularity and lookahead in the performance and development of the Type I IF, and to discuss possible methods to automate the capture of appropriate values of lookahead. 相似文献
7.
A comprehensive approach for the eigenproblem of beams with arbitrary boundary conditions 总被引:2,自引:0,他引:2
K. H. Low 《Computers & Structures》1991,39(6):671-678
A fundamental but reliable and comprehensive approach of obtaining the exact roots for the frequency equation of given beam systems is presented. The frequency equation is incorporated with the boundary conditions, which depend on the physical components attached to the beam's ends. The eigenvalues are evaluated without knowing the explicit form of the frequency equation. The validity of the proposed algorithm is confirmed by considering an illustrated model with three case studies. 相似文献
8.
Welch G. State A. Ilie A. Kok-Lim Low Lastra A. Cairns B. Towles H. Fuchs H. Ruigang Yang Becker S. Russo D. Funaro J. van Dam A. 《Multimedia, IEEE》2005,12(3):22-35
Immersive electronic books (IEBooks) for surgical training will let surgeons explore previous surgical procedures in 3D. The authors describe the techniques and tools for creating a preliminary IEBook, embodying some of the basic concepts. 相似文献
9.
This is an ECG of a 6-year-old girl. She presented to us for management of epilepsy. Magnetic resonance imaging (MRI) of the brain showed multiple lesions consistent with cortical and subcortical tubers. There were also achromic spots on her skin and echocardiography demonstrated a rhabdomyoma near the right ventricular outflow tract. A diagnosis of tuberous sclerosis, an autosomal-dominantly inherited condition, was made. What is abnormal about the ECG? 相似文献
10.