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281.
To evaluate the use of multi-frequency, polarimetric Synthetic Aperture Radar (SAR) data for quantifying the above ground biomass (AGB) of open forests and woodlands, NASA JPL AIRSAR (POLSAR) data were acquired over a 37 × 60 km area west of Injune, central Queensland, Australia. From field measurements recorded within 32 50 × 50 m plots, AGB was estimated by applying species-specific allometric equations to stand measurements. AGB was then scaled-up to the larger area using relationships established with Light Detection and Ranging (LiDAR) data acquired over 150 (10 columns, 15 rows) 500 × 150 m cells (or Primary Sampling Units, PSUs) spaced 4 × 4 km apart in the north- and east-west directions. Large-scale (1 : 4000) stereo aerial photographs were also acquired for each PSU to assess species composition. Based on the LiDAR extrapolations, the median AGB for the PSU grid was 82 Mg ha− 1 (maximum 164 Mg ha− 1), with the higher levels associated with forests containing a high proportion of Angophora and Callitris species. Empirical relationships between AGB and SAR backscatter confirmed that C-, L- and P-band saturated at different levels and revealed a greater strength in the relationship at higher incidence angles and a larger dynamic range and consistency of relationships at HV polarizations. A higher level of saturation (above ∼50 Mg ha− 1) was observed at C-band HV compared to that reported for closed forests which was attributable to a link between foliage projected cover (FPC) and AGB. The study concludes that L-band HV backscatter data acquired at incidence angles approaching or exceeding 45° are best suited for estimating the AGB up to the saturation level of ∼80-85 Mg ha− 1. For regional mapping of biomass below the level of saturation, the use of the Japanese Space Exploration Agency (JAXA) Advanced Land Observing Satellite (ALOS) Phase Arrayed L-band SAR (PALSAR) is advocated. 相似文献
282.
Kirilova Elisaveta Vaklieva-Bancheva Natasha Vladova Rayka Petrova Tatyana Ivanov Boyan Nikolova Desislava Dzhelil Yunzile 《Clean Technologies and Environmental Policy》2022,24(1):213-227
Clean Technologies and Environmental Policy - The production of dairy products is related to water and energy costs and generation of large amounts of emissions of pollutants. Full sustainability... 相似文献
283.
Susanne M. M. de Mooij Maartje E. J. Raijmakers Iroise Dumontheil Natasha Z. Kirkham Han L. J. van der Maas 《Journal of Computer Assisted Learning》2021,37(1):242-252
While response time and accuracy indicate overall performance, their value in uncovering cognitive processes, underlying learning, is limited. A promising online measure, designed to track decision-making, is computer mouse tracking, where mouse attraction towards different locations may reflect the consideration of alternative response options. Using a speedy arithmetic multiple-choice game in an online adaptive learning environment, we examined whether mouse movements could reflect arithmetic difficulties when error rates are low. Results showed that mouse movements towards alternative responses in correctly answered questions mapped onto the frequency of errors made in this online learning system. This mapping was stronger for the younger children, as well as for easy arithmetic problems. On an individual level, users showed more mouse movement towards their previously made response errors than towards other alternative options. This opens the possibility of adapting feedback and instruction on an individual basis through mouse tracking. 相似文献
284.
Nadler Natasha; Delgado Mauricio R.; Delamater Andrew R. 《Canadian Metallurgical Quarterly》2011,11(5):1112
Pavlovian learning tasks have been widely used as tools to understand basic cognitive and emotional processes in humans. The present studies investigated one particular task, Pavlovian-to-instrumental transfer (PIT), with human participants in an effort to examine potential cognitive and emotional effects of Pavlovian cues upon instrumentally trained performance. In two experiments, subjects first learned two separate instrumental response-outcome relationships (i.e., R1-O1 and R2-O2) and then were exposed to various stimulus-outcome relationships (i.e., S1-O1, S2-O2, S3-O3, and S4-) before the effects of the Pavlovian stimuli on instrumental responding were assessed during a non-reinforced test. In Experiment 1, instrumental responding was established using a positive-reinforcement procedure, whereas in Experiment 2, a quasi-avoidance learning task was used. In both cases, the Pavlovian stimuli exerted selective control over instrumental responding, whereby S1 and S2 selectively elevated the instrumental response with which it shared an outcome. In addition, in Experiment 2, S3 exerted a nonselective transfer of control effect, whereby both responses were elevated over baseline levels. These data identify two ways, one specific and one general, in which Pavlovian processes can exert control over instrumental responding in human learning paradigms, suggesting that this method may serve as a useful tool in the study of basic cognitive and emotional processes in human learning. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
285.
Cabrera Natasha J.; Ryan Rebecca M.; Mitchell Stephanie J.; Shannon Jacqueline D.; Tamis-LeMonda Catherine S. 《Canadian Metallurgical Quarterly》2008,22(4):643
Using data from a racially and ethnically diverse sample of low-income mothers of 2-year-old children participating in the Early Head Start Research and Evaluation Project (N = 883), the authors examined fathers' education and employment, mother-father relationship, and mothers' relationships with kin in the household to explain variation in nonresident father involvement across racial and ethnic groups. Nonresident White fathers were less involved with their children than were African American and Latino fathers. This difference was explained by the status of mother-father relationships. White nonresident fathers were less likely than minority nonresident fathers to maintain romantic relationships with their child's mother. Mothers in the White father group were also more likely to re-partner, which negatively related to biological fathers' involvement. These findings suggest that approaches to strengthen nonresident father involvement in children's lives need to consider how father ethnicity and mother-father relations are associated with differential patterns of father involvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
286.
It is pointed out by Jiang and Wang (2005) [1], that the conversion formula from Bernstein into DP bases is incorrect for all even degrees and the conversion formula from DP into Bernstein bases is incorrect for every degree. Thus, in this paper we give some notes, corrections and new proofs for the relationship between these two NTP bases. 相似文献
287.
Mieow Kee Chan Prasilla Kumaran Xavier Vigneswaran Thomas Eva Natasha Yi Shen Tee Alijah Mohd Aris Yoke Ping Ho Bee Chin Khor 《加拿大化工杂志》2023,101(7):3751-3758
Bimetallic nanoparticles have been widely studied for wastewater treatment, but the study of nanoFeCu for sewage treatment is minimal. In the previous work, ammonia was removed by nanoFeCu via an oxidation reaction, and nitrogen gas was released. However, the performance and reusability of nanoFeCu in treating industrial wastewater have not been reported elsewhere. This study revealed the performance of nanoFeCu for sewage treatment on both laboratory-scale and pilot-scale for the first time. A varied mass of embedded nanoFeCu (eFeCu4) was exposed to sewage water, and the quality of the effluent was measured in terms of ammonia, biological oxygen demand (BOD), and chemical oxygen demand (COD) removal. Fe2+ and Cu2+ concentrations were measured to determine the stability of eFeCu4 in nine reuse cycles. Results showed that the laboratory-scale experiment removed 20%–30% ammonia from sewage. A similar removal rate was reported in all nine cycles of reuse, which confirmed the usability and reliability of eFeCu4. In the pilot-scale study, ammonia was removed from ~22.3 to ~4.8 mg/L, while BOD and COD were reduced from ~204 to ~56 mg/L and ~71 to ~39.7 mg/L, respectively. The treated effluent quality complies with the effluent discharge standard of Malaysia, and it is also comparable with the effluent quality at sewage treatment plants in Malaysia and overseas. In conclusion, nanoFeCu could be an alternative method for sewage treatment due to its stability and pollutant removal performance. A sustainability and cost-effectiveness study should be conducted to determine the feasibility of a full-scale application. 相似文献
288.
Spencer Larkin Natasha Kyprianou 《International journal of molecular sciences》2013,14(9):18421-18436
Urologic tumors continue to represent a huge fraction of cancer cases in the United States, with over 376,310 estimated new diagnoses in 2013. As with many types of tumors, urologic tumors vary greatly in their phenotype, ranging from minimally invasive to malignancies possessing great metastatic potential. The increasing need for more efficient and less invasive methods of cancer detection, as well as the ability to predict severity of the disease phenotype is readily evident—yet reliable methods remain elusive in a clinical setting today. Comprehensive panels of gene clusters are being developed toward the generation of molecular signatures in order to better diagnose urologic malignancies, and identify effective treatment strategies in the emerging era of personalized medicine. In this review, we discuss the current literature on the credibility and biomarker value of such molecular signatures in the context of clinical significance relating to the pathological aggressiveness of urologic tumors (prostate, bladder and renal cancer)—also exploiting their predictive potential in the response to treatment. 相似文献
289.
Currently, wireless communications are changing along the lines of three main thrusts. The first is the introduction of secondary
spectrum licensing (SSL). Regulations on the usage of licensed spectra are being loosened, encouraging unused primary spectrum
to be licensed, often in an opportunistic manner, to secondary devices. The second is the introduction of cognitive radios. These wireless devices are able to sense and adapt in a “smart” manner to their wireless environment, making them prime
candidates to becoming secondary users in SSL initiatives. Finally, as we approach the communication limits of point-to-point
channels, and as wireless devices become cheap and ubiquitous, the focus is shifting from single to multiple communication
links, or networks. In this paper, we provide an overview of the recently established theoretical limits, in the form of sum-rates, or throughput,
of two main types of networks: ad hoc networks, in which the devices are homogeneous, and cognitive networks, in which a mixture
of primary and secondary (or cognitive) devices are present. We summarize and provide intuition on how the throughput of a
network scales with its number of nodes n, as n → ∞, under different network and node capability assumptions.
相似文献
Mai VuEmail: |