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11.
Dynamics of urban growth in the Washington DC metropolitan area, 1973-1996, from Landsat observations 总被引:1,自引:0,他引:1
J. G. Masek F. E. Lindsay S. N. Goward 《International journal of remote sensing》2013,34(18):3473-3486
Like other human-induced landcover changes, urbanization represents a response to specific economic, demographic, or environmental conditions. We use the Washington D.C. area as a case study to relate satellite-derived estimates of urban growth to these economic and demographic drivers. Using the Landsat data archive we have created a three epoch timeseries for urban growth for the period 1973-1996. This map is based on a NDVI-differencing approach for establishing urban change filtered with a landcover classification to minimize confusion with agriculture. Results show that the built-up area surrounding Washington DC has expanded at a rate of ~22km2 per year during this period, with notably higher growth during the late-1980s. Comparisons with census data indicate that the physical growth of the urban plan, observable from space, can be reasonably correlated with regional and national economic patterns. 相似文献
12.
Hirshfeld-Becker Dina R.; Masek Bruce; Henin Aude; Blakely Lauren Raezer; Pollock-Wurman Rachel A.; McQuade Julia; DePetrillo Lillian; Briesch Jacquelyn; Ollendick Thomas H.; Rosenbaum Jerrold F.; Biederman Joseph 《Canadian Metallurgical Quarterly》2010,78(4):498
Objective: To examine the efficacy of a developmentally appropriate parent–child cognitive behavioral therapy (CBT) protocol for anxiety disorders in children ages 4–7 years. Method: Design: Randomized wait-list controlled trial. Conduct: Sixty-four children (53% female, mean age 5.4 years, 80% European American) with anxiety disorders were randomized to a parent–child CBT intervention (n = 34) or a 6-month wait-list condition (n = 30). Children were assessed by interviewers blind to treatment assignment, using structured diagnostic interviews with parents, laboratory assessments of behavioral inhibition, and parent questionnaires. Analysis: Chi-square analyses of outcome rates and linear and ordinal regression of repeated measures, examining time by intervention interactions. Results: The response rate (much or very much improved on the Clinical Global Impression Scale for Anxiety) among 57 completers was 69% versus 32% (CBT vs. controls), p 相似文献
13.
This paper mainly studies the multi‐objective optimization of load dispatch of power systems including renewable energy and CO2 capture and storage (CCS) technologies. The improved environmental/economic load dispatch model for the power system is constructed, considering the renewable energy utilization and CCS technologies. A novel singular weighted method (SWM) has been proposed in this paper for solving this kind of multi‐objective and multi‐constraint optimization problem. A power system with five generators has been applied in one case study to test the model and SWM. It was concluded that the share that each unit takes is not linear; however, the optimal results are largely relevant to the characteristics of the units. In addition, the research results showed that with the increment of the weight coefficient for a certain objective function, the optimization result was closer to the single optimization result for that objective function; and with the increase of forecast demand load, a 35 MW wind energy unit and a 200 MW water energy unit should be built. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
14.
Feng Gao Eric Brown de Colstoun Ronghua Ma Qihao Weng Jeffrey G. Masek Jin Chen 《International journal of remote sensing》2013,34(24):7609-7628
Cities have been expanding rapidly worldwide, especially over the past few decades. Mapping the dynamic expansion of impervious surface in both space and time is essential for an improved understanding of the urbanization process, land-cover and land-use change, and their impacts on the environment. Landsat and other medium-resolution satellites provide the necessary spatial details and temporal frequency for mapping impervious surface expansion over the past four decades. Since the US Geological Survey opened the historical record of the Landsat image archive for free access in 2008, the decades-old bottleneck of data limitation has gone. Remote-sensing scientists are now rich with data, and the challenge is how to make best use of this precious resource. In this article, we develop an efficient algorithm to map the continuous expansion of impervious surface using a time series of four decades of medium-resolution satellite images. The algorithm is based on a supervised classification of the time-series image stack using a decision tree. Each imerpervious class represents urbanization starting in a different image. The algorithm also allows us to remove inconsistent training samples because impervious expansion is not reversible during the study period. The objective is to extract a time series of complete and consistent impervious surface maps from a corresponding times series of images collected from multiple sensors, and with a minimal amount of image preprocessing effort. The approach was tested in the lower Yangtze River Delta region, one of the fastest urban growth areas in China. Results from nearly four decades of medium-resolution satellite data from the Landsat Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper plus (ETM+) and China–Brazil Earth Resources Satellite (CBERS) show a consistent urbanization process that is consistent with economic development plans and policies. The time-series impervious spatial extent maps derived from this study agree well with an existing urban extent polygon data set that was previously developed independently. The overall mapping accuracy was estimated at about 92.5% with 3% commission error and 12% omission error for the impervious type from all images regardless of image quality and initial spatial resolution. 相似文献
15.
Alexander Pyattaev Jiri Hosek Kerstin Johnsson Radko Krkos Mikhail Gerasimenko Pavel Masek Aleksandr Ometov Sergey Andreev Jakub Sedy Vit Novotny Yevgeni Koucheryavy 《ETRI Journal》2015,37(5):877-887
This paper is a first‐hand summary on our comprehensive live trial of cellular‐assisted device‐to‐device (D2D) communications currently being ratified by the standards community for next‐generation mobile broadband networks. In our test implementation, we employ a full‐featured 3GPP LTE network deployment and augment it with all necessary support to provide real‐time D2D connectivity over emerging Wi‐Fi‐Direct (WFD) technology. As a result, our LTE‐assisted WFD D2D system enjoys the required flexibility while meeting the existing standards in every feasible detail. Further, this paper provides an account on the extensive measurement campaign conducted with our implementation. The resulting real‐world measurements from this campaign quantify the numerical effects of D2D functionality on the resultant system performance. Consequently, they shed light on the general applicability of LTE‐assisted WFD solutions and associated operational ranges. 相似文献
16.
The literature data assembled in this article document the variation of immunobiological effects of nitric oxide (NO). A number of factors are obviously responsible for the diversity, ranging from inactivity, alleviation, but not rarely to exacerbation of certain pathogenetic processes. A better understanding of NO interactions with the immune system can only be reached if more complex experimental designs to study the effects of reactive nitrogen species are adopted in the future. They should integrate major participating variables and take into account pharmacodynamic/kinetic aspects of NO production in triggering the ultimate effects. If manipulation of NO in the organism by means of recently developed NO inhibitors and NO donors is to become a rational tool of immunopharmacological strategies, detailed knowledge of their pharmacologies and toxicologies is urgently needed in order to differentiate between the effects of NO and other side effects. Hopefully, this approach could improve the predictability of the clinical outcomes of NO manipulation. 相似文献
17.
Anna Masek Stefan Cichosz Magorzata Piotrowska 《International journal of molecular sciences》2021,22(6)
The study aimed to prepare sustainable and degradable elastic blends of epoxidized natural rubber (ENR) with poly(lactic acid) (PLA) that were reinforced with flax fiber (FF) and montmorillonite (MMT), simultaneously filling the gap in the literature regarding the PLA-containing polymer blends filled with natural additives. The performed study reveals that FF incorporation into ENR/PLA blend may cause a significant improvement in tensile strength from (10 ± 1) MPa for the reference material to (19 ± 2) MPa for the fibers-filled blend. Additionally, it was found that MMT employment in the role of the filler might contribute to ENR/PLA plasticization and considerably promote the blend elongation up to 600%. This proves the successful creation of the unique and eco-friendly PLA-containing polymer blend exhibiting high elasticity. Moreover, thanks to the performed accelerated thermo-oxidative and ultraviolet (UV) aging, it was established that MMT incorporation may delay the degradation of ENR/PLA blends under the abovementioned conditions. Additionally, mold tests revealed that plant-derived fiber addition might highly enhance the ENR/PLA blend’s biodeterioration potential enabling faster and more efficient growth of microorganisms. Therefore, materials presented in this research may become competitive and eco-friendly alternatives to commonly utilized petro-based polymeric products. 相似文献
18.
Concepts from the Australian mathematics curriculum on fractions were used as core elements to design three computer games. In each game, the concepts were presented in the form of tangible puzzles, customized to a difficulty level based on student capability. The games were integrated into a single virtual game world, and a fantasy story was used to help build a compelling experience. Five Year 6 classes were used to evaluate the game over four weeks. Three of the classes were provided with the games, and two served as a control. Both the intervention and control groups also covered fractions in class as part of the regular teaching program, consisting of instructor led content combined with access to online resources and activities. Participants completed a diagnostic test before the trial, and again at the end, designed to assess competence in the fractions concepts targeted by the game. Results show that on average students who had access to the game in addition to the regular teaching scored higher than control group students. In particular, looking at just students who started with a lower level of fractions skills, greater improvement was seen in those that had access to the game. 相似文献
19.
Anna Masek Stefan Cichosz Magorzata Piotrowska 《International journal of molecular sciences》2021,22(23)
The effects of plant-based extracts on the solar aging and antimicrobial properties of impregnated ethylene–norbornene (EN) copolymer and poly(lactic acid) (PLA) were investigated. In this study, the impregnation yield of polyolefin, lacking in active centers capable of phytochemical bonding, and polyester, abundant in active sides, was measured. Moreover, two different extracts plentiful in phytochemicals—thyme (TE) and clove (CE)—were employed in the solvent-based impregnation process. The effect of thymol and eugenol, the two main compounds embodied in the extracts, was studied as well. Interestingly, oxidation induction times (OIT) for the impregnation of EN with thyme and clove extracts were established to be, respectively, 27.7 and 39.02 min, which are higher than for thymol (18.4 min) and eugenol (21.1 min). Therefore, an aging experiment, mimicking the full spectrum of sunlight, was carried out to investigate the resistance to common radiation of materials impregnated with antioxidative substances. As expected, the experiment revealed that the natural extracts increased the shelf-life of the polymer matrix by inhibiting the degradation processes. The aging resistance was assessed based on detected changes in the materials’ behavior and structure that were examined with Fourier-transform infrared spectroscopy, contact angle measurements, color quantification, tensile tests, and hardness investigation. Such broad results of solar aging regarding materials impregnated with thyme and clove extracts have not been reported to date. Moreover, CE was found to be the most effective modifying agent for enabling material with antimicrobial activity against Escherichia coli to be obtained. 相似文献
20.
Over the past 25 years, cannabis plants have gained major popularity in the research community. This study aimed to evaluate the antioxidant capacity and stabilization efficiency of cannabidiol (CBD) extract in two different polymers: polylactide (PLA) and ethylene–norbornene copolymer (Topas) that are used in packaging materials more often. The research technology included weathering in a special chamber, surface free energy and color change measurements, surface morphology and Fourier-transform infrared spectroscopy (FTIR) analysis, thermogravimetry, and determination of the oxidation induction time or temperature (OIT) values, based on which the effectiveness of the cannabidiol extract could be estimated. Obtained results showed that the addition of CBD to polymer mixtures significantly increased their resistance to oxidation, and it can be used as a natural stabilizer for polymeric products. Moreover, samples with cannabidiol changed their coloration as a result of weathering. Therefore, this natural additive can also be considered as a colorimetric indicator of aging that informs about the changes in polymeric materials during their lifetime. On the other hand, surface properties of samples with cannabidiol content did not alter much compared to pure Topas and PLA. 相似文献