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131.
132.
Minimally invasive techniques are rapidly replacing traditional practices because they result in improved benefits for patients, health care providers, payers, employers and hospitals. While two-dimensional (2D) imaging has been used to guide interventional procedures for many decades, the use of three-dimensional (3D) imaging of the anatomy has the potential to provide more accurate and less variable interventional guidance and monitoring options. Although 3D magnetic resonance imaging (MRI), computed tomography (CT) and angiography are important modalities, the development of 3D ultrasound imaging techniques that are capable of acquiring B-mode, color Doppler and power Doppler images, has allowed the development of image-guided therapy and surgery approaches that are making breast biopsy and prostate therapy more accurate and less variable. The use of 3D ultrasound has the potential to provide inexpensive and near real-time views of the anatomy and pathology enabling minimally invasive interventional procedures. In this paper we present the principles and advantages of 3D ultrasound imaging, review some of the implementations techniques, and present new applications in image-guided prostate therapy and breast biopsy. 相似文献
133.
Influence of Data Clouds Fusion From 3D Real-Time Vision System on Robotic Group Dead Reckoning in Unknown Terrain
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Mykhailo Ivanov Oleg Sergyienko Vera Tyrsa Lars Lindner Wendy Flores-Fuentes Julio Cesar Rodriguez-Quinonez Wilmar Hernandez Paolo Mercorelli 《IEEE/CAA Journal of Automatica Sinica》2020,7(2):368-385
This paper proposes the solution of tasks set required for autonomous robotic group behavior optimization during the mission on a distributed area in a cluttered hazardous terrain.The navigation scheme uses the benefits of the original real-time technical vision system(TVS)based on a dynamic triangulation principle.The method uses TVS output data with fuzzy logic rules processing for resolution stabilization.Based on previous researches,the dynamic communication network model is modified to implement the propagation of information with a feedback method for more stable data exchange inside the robotic group.According to the comparative analysis of approximation methods,in this paper authors are proposing to use two-steps post-processing path planning aiming to get a smooth and energy-saving trajectory.The article provides a wide range of studies and computational experiment results for different scenarios for evaluation of common cloud point influence on robotic motion planning. 相似文献
134.
AbstractCritical infrastructure (CI) has received much attention in research, policy and political discussions in recent years, following concern over exposure of infrastructure to terrorist attack, disruption through disasters, rising awareness of the interdependent nature of infrastructure in modern urban systems, and changes in the ownership of and responsibility for infrastructure assets. In this paper, we explore the implications of different framings of both “critical” and “infrastructure”, through two questions: critical how and for whom; critical when and at what scale? Framings of CI, and their increasingly important manifestations in policy and law, have deep but too-often unexposed implications: the lines drawn between what is defined as critical and that which is not concerns not only the physical or informational assets, but the inclusion/exclusion of communities and their places and values as important aspects of modern urban governance. We argue that a better understanding of what is critical about urban infrastructure is not just recognition of their vulnerability and interconnectedness, but also of the key linkages between critical infrastructure and human and environmental system integrity and equity within the context of capitalist urbanisation. 相似文献
135.
Urban vegetation increasingly contributes to nature conservation and ecosystem services, but lacking understanding of site variations has restricted such uses. This study analyzed the spatial pattern and differentiation of tree communities in three major green landscape types (urban parks, riverside parks and street verges) in Taipei city. In each landscape type, 10 representative tree communities were studied. Statistical tests for ecological communities were employed: Jaccard and Q species similarity indices, two-way indicator species analysis (TWINSPAN), and new species fidelity, landscape fidelity and composite Q indices. Significant recent increase in Taipei's green spaces was traced. The study area contained 164 tree species, but few were shared by the three landscape types and none by 30 communities. Native evergreen broadleaf species with large final dimensions were dominant. Urban parks registered the highest species richness, landscape fidelity, rare species and urban endemics. Such exclusive species constitution deviated notably from riverside parks and street verges, with relatively simple and converging intra-site species ingredients. Pronounced species differentiation between urban parks reflected diversified site topography, natural woodland inheritance, woodland creation, and past landscape fashion. TWINSPAN classified the communities into nine groups each with signature characteristics. Inherent site variations offered main determinants of tree heterogeneity, superimposed by human modification to satisfy pre-determined site functions. A hybrid urban park with high species diversity and nature contents is advocated by amalgamating conventional but polarized designs of country and urban parks. The findings could inform management of urban forest, urban nature conservation, and ecological services of urban green spaces. 相似文献
136.
Nutrient budget for Saguling Reservoir,West Java,Indonesia 总被引:2,自引:0,他引:2
A preliminary nutrient budget for Saguling Reservoir is reported as a first attempt to quantify the behaviour of nutrients entering this reservoir. This work is part of a larger Indonesia-Australia collaborative research and training project, involving Padjadjaran University and Monash University, established to study nutrient dynamics in Saguling Reservoir. Saguling Reservoir, the first of a chain of three large reservoirs (Saguling, Cirata and Jatilahur), built on the Citarum River in central Java, was completed in 1985. It has already become highly polluted, particularly with domestic and industrial effluent (organic matter, nutrients, heavy metals) from the urban areas of Bandung (population 2 million). The reservoir experiences major water quality problems, including excessive growths of floating plants, toxic cyanobacterial blooms and regular fish-kills. The work reported in this paper shows that Saguling receives a very large nutrient load from the city of Bandung and because of this, is highly eutrophic. It is unlikely that the water quality of Saguling will improve until a substantial part of Bandung is sewered and adequate discharge controls are placed on the many industries in the region upstream of the reservoir. 相似文献
137.
This analysis of HF/E literature on preferences for text entry distills the findings to guide designers in applying optimum solutions for devices such as PDAs and cell phones. 相似文献
138.
Wendy L. St. PETER Jiannong LIU Eric D. WEINHANDL Qiao FAN 《Hemodialysis international. International Symposium on Home Hemodialysis》2008,12(4):480-491
The Dialysis Clinical Outcomes Revisited (DCOR) trial was a large randomized, multicenter 3‐year trial comparing the effects of sevelamer with calcium‐based binders on mortality, hospitalization, morbidity, and medical costs in hemodialysis subjects. Dialysis Clinical Outcomes Revisited was prospectively designed to link subjects to the Centers for Medicare & Medicaid Services End‐Stage Renal Disease (CMS ESRD) database to collect additional baseline characteristic data and to enhance outcome evaluation. Subjects were linked to the CMS ESRD database by means of an algorithm using several patient identifiers. Some baseline characteristic data were collected exclusively from the CMS ESRD database. Mortality and hospitalization end points were obtained from the CMS ESRD database and compared with similar data collected prospectively into a case‐report form (CRF) database. Of the 2103 patients who participated in the DCOR study, 2101 were successfully linked to the CMS ESRD database. Patient baseline data showed that treatment groups were well‐balanced, except that a higher proportion of subjects in the calcium‐based binder group had atherosclerotic heart disease. Calculated mortality rates were similar between databases, but more deaths were identified in the CMS than in the CRF database. These additional deaths were verified through several sources. More hospitalizations were also detected in the CMS than in the CRF database. The CMS database was a good source of death end points and hospitalization occurrence. Linking patients to the data‐rich CMS ESRD database allowed assessment of additional important secondary end points at a relatively low cost compared with prospective data collection. 相似文献
139.
Seven challenges for nanomedicine 总被引:1,自引:0,他引:1
140.
Meier Madeline H.; Slutske Wendy S.; Arndt Stephan; Cadoret Remi J. 《Canadian Metallurgical Quarterly》2008,117(2):377
The purpose of the present study was to determine whether the effect of impulsive and callous personality traits on delinquent behavior varied across neighborhood context in a population-based, statewide sample of 85,000 Iowa schoolchildren ages 10-19. Two previous studies examining the association between impulsivity and delinquency across disadvantaged and affluent neighborhoods have yielded contrasting findings. Results of the present study suggested a robust moderating effect of neighborhood context on personality risk for delinquency. The relation between impulsivity and delinquency was greater in neighborhoods low in collective efficacy compared to neighborhoods high in collective efficacy. A similar interaction was found for callous personality traits, indicating the consistency of the moderating effect of neighborhood context on personality risk for delinquency. Gender differences were also examined, and results were replicated in a holdout sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献