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Number of results: 8
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Abstract

This paper present the data for monitoring forest conditions and forest resource management by a local community adjacent to the Doi Laung Wildlife Sanctuary, Huaimai Sub-district, Song District, Phrae Province, Thailand. This study uses quantitative forest surveys, interviews, discussions, and descriptions of the historical context of public participation in forest management including a detailed assessment of field conditions. The findings of a forest resources inventory show that (1) from the three sampled areas, Doi Laung Wildlife Sanctuary has highest richness, followed by village #16 and #14, and (2) Huaikhon #16 implied the process of framework to maintain a healthy condition and response to community needs with collective management. The conceptual model assessment that links key group indicators and drivers is presented based on previously developed assessment models. The framework focuses on the best way to provide forest management, forest fire prevention, and firefighting as well as monitoring of Check-dam construction and other activities that support the recovery of the forest community. This paper demonstrates the general of an environmental assessment framework to applying organize environmental information to facilitate policy decision making for the sustainable development.
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Abstract

Lichens, as typical obligate associations between lichenized fungi and their photosynthetic partners, are dominant in Antarctica. Three Antarctic lichens, Ochrolechia frigida , Umbilicaria antarctica , and Usnea aurantiaco−atra with different growth forms, were sampled nearby the Great Wall Station, King George Island. Molecular data revealed that the photosynthetic algae in these three lichens were Trebouxia jamesii . The net photo − synthesis (Pn) of three individuals from these species, together with environmental factors such as light and temperature, were recorded by CO 2 gas exchange measurements using a CI−340 portable photosynthetic system in situ . Differences between T(leaf) (the temperature of the thalli) and T(air) (the air temperature) for these lichens were not consistent, which reflected that environment and the growth form of thalli could affect T(leaf) significantly. Strong irradiation was expected to have adverse effects on Pn of Ochrolechia frigida and Umbilicaria antarctica whose thalli spread flat; but this photoinhibition had little effect on Usnea aurantiaco−atra with exuberant tufted thallus. These results indicated that photo − synthetic activity in lichens was affected by the growth forms of thalli besides microhabitat factors. One species of lichenized alga could exhibit diversified types of photosynthetic behavior when it was associated with various lichenized fungi in different microhabitats. It will be helpful for understanding how lichens are able to adapt to and colonize in extreme environments.
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Abstract

The advance of MEMS-based inertial sensors successfully expands their applications to small unmanned aerial vehicles (UAV), thus resulting in the challenge of reliable and accurate in-flight alignment for airborne MEMS-based inertial navigation system (INS). In order to strengthen the rapid response capability for UAVs, this paper proposes a robust in-flight alignment scheme for airborne MEMS-INS aided by global navigation satellite system (GNSS). Aggravated by noisy MEMS sensors and complicated flight dynamics, a rotation-vector-based attitude determination method is devised to tackle the in-flight coarse alignment problem, and the technique of innovation-based robust Kalman filtering is used to handle the adverse impacts of measurement outliers in GNSS solutions. The results of flight test have indicated that the proposed alignment approach can accomplish accurate and reliable in-flight alignment in cases of measurement outliers, which has a significant performance improvement compared with its traditional counterparts.
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Abstract

The main optimized objects in underground mines include: stope layout, access layout and production scheduling. It is common to optimize each component sequentially, where optimal results from one phase are regarded as the input data for the next phase. Numerous methods have been developed and implemented to achieve the optimal solution for each component. In fact, the interaction between different phases is ignored in the tradition optimization models which only get the suboptimal solution compared to the integrated optimization model. This paper proposes a simultaneous integrated optimization model to optimize the three components at the same time. The model not only optimizes the mining layout to maximize the Net Present Value (NPV), but also considers the extension sequence of stope extraction and access excavation. The production capacity and ore quality requirement are also taken into account to keep the mining process stable in all mine life. The model is validated to a gold deposit in China. A two-dimensional block model is built to do the resource estimation due to the clear boundary of the hanging wall and footwall. The thickness and accumulation of each block is estimated by Ordinary Kriging (OK). In addition, the conditional simulation method is utilized to generate a series of orebodies with equal possibility. The optimal solution of optimization model is carried out on each simulated orebody to evaluate the influence of geological uncertainty on the optimal mining design and production scheduling. The risk of grade uncertainty is quantified by the possibility of obtaining the expected NPV. The results indicate that the optimization model has the ability to produce an optimal solution that has a good performance under the uncertainty of grade variability.
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Abstract

Due to the difficulty of detecting traces of organic acid mixture in an aqueous sample and the complexity of resolving UV-Vis spectra effectively, a combinatory method based on a self-made radical electric focusing solid phase extraction (REFSPE) device, UV-Vis detection and partial least squares (PLS) calculation is proposed here. In this study, REFSPE was used to enhance the extraction process of analytes between the aqueous phase and the membrane phase to enrich the trace of mixed organic acid efficiently. Then, the analytes, which were eluted from the adsorption film by ethanol with the assistance of an ultrasonic cleaning machine, were detected with UV-Vis spectrophotometry. After that, the PLS method was introduced to solve the problem of overlapping peaks in UV-Vis spectra of mixed substances and to quantify each compound. The linearly dependent coefficients between the predicted value of the model and the actual concentration of the sample were all higher than 0.99. The limit values of detection for benzoic acid, phthalic acid and p-toluene sulfonic acid were found at 9.9 #22;g/L, 12.2 #22;g/L and 13.8 #22;g/L with the relative recovery values between 84.8% and 117.9%. The RSD (n = 20) values of each component are 1.17%, 1.11% and 0.86%, respectively. Therefore, the proposed combined method can determine traces of complex materials in an aqueous sample efficiently and has wonderful potential applications.
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Abstract

Sample-time errors can greatly degrade the dynamic range of a time-interleaved sampling system. In this paper, a novel correction technique employing a cubic spline interpolation is proposed for inter-channel sample-time error compensation. The cubic spline interpolation compensation filter is developed in the form of a finite-impulse response (FIR) filter structure. The correction method of the interpolation compensation filter coefficients is deduced. A 4GS/s two-channel, time-interleaved ADC prototype system has been implemented to evaluate the performance of the technique. The experimental results showed that the correction technique is effective to attenuate the spurious spurs and improve the dynamic performance of the system.
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