A novel active power decoupling converter (APDC) applied in power factor correction (PFC) converter is proposed, which overcomes the problem that the DC‐link voltage ripple of small capacitor PFC ...converters depend heavily on the consistency of capacitors. The proposed APDC consists of a boost circuit and a pulsating power buffer circuit, and the DC link is composed of two asymmetric film split capacitors connected in series. The former controls the grid quality, and the latter controls voltages complementary to suppress the DC‐link voltage ripple. Experiments verify the effectiveness of the proposed PFC converter.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Reported herein is an asymmetric Pd/PC‐Phos‐catalyzed denitrogenative cyclization of benzotriazoles with allenes and N‐allenamides, representing the first example of enantioselective denitrogenative ...cyclizations of benzotriazoles. A series of optically active 3‐methyleneindolines were obtained in good yields with high ee values. The use of inexpensive and readily available starting materials, high regio‐ and enantioselectivity, a broad substrate scope, mild reaction conditions, no need for base, as well as versatile functionalization of the 3‐methyleneindolines make this approach attractive.
The first example of an enantioselective denitrogenative cyclization of benzotriazoles with allenes and N‐allenamides is enabled using Pd/PC‐Phos catalysis, and provides rapid access to optically active 3‐methyleneindolines in good yields with high ee values. The method features a general substrate scope, high regioselectivity, and mild reaction conditions. Tf=trifluoromethanesulfonyl.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The energy sector is a major user of fresh water resources in China. We investigate the life cycle water withdrawals, consumptive water use, and wastewater discharge of China’s energy sectors and ...their water-consumption-related environmental impacts, using a mixed-unit multiregional input–output (MRIO) model and life cycle impact assessment method (LCIA) based on the Eco-indicator 99 framework. Energy production is responsible for 61.4 billion m3 water withdrawals, 10.8 billion m3 water consumption, and 5.0 billion m3 wastewater discharges in China, which are equivalent to 12.3%, 4.1% and 8.3% of the national totals, respectively. The most important feature of the energy–water nexus in China is the significantly uneven spatial distribution of consumptive water use and its corresponding environmental impacts caused by the geological discrepancy among fossil fuel resources, fresh water resources, and energy demand. More than half of energy-related water withdrawals occur in the east and south coastal regions. However, the arid north and northwest regions have much larger water consumption than the water abundant south region, and bear almost all environmental damages caused by consumptive water use.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Evolutionary histories can be discordant across the genome, and such discordances need to be considered in reconstructing the species phylogeny. ASTRAL is one of the leading methods for inferring ...species trees from gene trees while accounting for gene tree discordance. ASTRAL uses dynamic programming to search for the tree that shares the maximum number of quartet topologies with input gene trees, restricting itself to a predefined set of bipartitions.
We introduce ASTRAL-III, which substantially improves the running time of ASTRAL-II and guarantees polynomial running time as a function of both the number of species (n) and the number of genes (k). ASTRAL-III limits the bipartition constraint set (X) to grow at most linearly with n and k. Moreover, it handles polytomies more efficiently than ASTRAL-II, exploits similarities between gene trees better, and uses several techniques to avoid searching parts of the search space that are mathematically guaranteed not to include the optimal tree. The asymptotic running time of ASTRAL-III in the presence of polytomies is Formula: see text where D=O(nk) is the sum of degrees of all unique nodes in input trees. The running time improvements enable us to test whether contracting low support branches in gene trees improves the accuracy by reducing noise. In extensive simulations, we show that removing branches with very low support (e.g., below 10%) improves accuracy while overly aggressive filtering is harmful. We observe on a biological avian phylogenomic dataset of 14K genes that contracting low support branches greatly improve results.
ASTRAL-III is a faster version of the ASTRAL method for phylogenetic reconstruction and can scale up to 10,000 species. With ASTRAL-III, low support branches can be removed, resulting in improved accuracy.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•State of the art of sensing materials for fruit freshness detection is reviewed.•Selection and modification of sensing materials of QCM sensors are presented.•Detection mechanisms of VOCs in fruit ...by QCM sensors are discussed.•Applications of QCM sensors for fruit freshness detection are reviewed.
In this review article, the state of the art of gas sensors based on quartz crystal microbalance (QCM) for fruit freshness detection is overviewed from the aspects of development history, working principle, selection and modification of sensitive materials, and volatile organic compounds detection of fruits. According to the characteristics of respiratory intensity at the stage of fruit ripening, fruits can be divided into respiration climacteric fruits and non-climacteric fruits. In recent years, research has mainly focused on respiration climacteric fruits, such as bananas and mangoes, etc., while related studies on non-climacteric fruits have been rarely reported, except for citrus fruits. The preparation methods and structure design of sensitive materials based on physical/chemical adsorption mechanisms are further discussed according to the odor components that affect the freshness of fruits, namely alkenes, esters, aldehydes and alcohols.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
China's booming economy has brought increasing pressures on its water resources. The water scarcity problem in China is characterized by a mismatch between the spatial distributions of water ...resources, economic development and other primary factors of production, which leads to the separation of production and consumption of water-intensive products. In this paper, we quantify the scale and structure of virtual water trade and consumption-based water footprints at the provincial level in China based on a multi-regional input–output model. We found that virtual water withdrawals and consumption embodied in domestic trade amounts to 184billionm3 and 101billionm3 in 2007, respectively, which is equivalent to 38% and 39% of national total fresh water withdrawals and consumption, respectively. Virtual water trade embodied in domestic trade is about two times as much as virtual water embodied in China's international exports. Water footprint in all four municipalities, i.e., Beijing, Tianjin, Shanghai and Chongqing, depends heavily on virtual water inflow from other provinces. China has a north-to-south net VWT pattern which is roughly the opposite of the distribution of its water resources. In addition to water efficiency improvement measures, re-shaping the water-trade nexus can be a significant complementary tool to address local water scarcity problems.
Inter-regional net virtual water trade in China in 2007. Display omitted
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Selecting appropriate reading materials for L2 (second language/foreign language) learners is crucial for improving their proficiency in the target language. However, the limitation of effective ...Chinese text readability classifiers poses a significant hurdle for students and educators in accurately gauging the precise difficulty level of texts in international Chinese education. This research conducted the readability grading of Chinese as a Second Language (CSL) texts by developing a BERT-Based CSL Readability Classifier (BCRC), which utilizes the BERT architecture specifically trained on CSL texts and incorporates multidimensional linguistic features including lexical richness, syntactic complexity and syntax patterns. The model was evaluated using a dataset of CSL texts, and the results indicate that the BCRC model performs effectively in predicting the readability levels of CSL texts. It achieves high mean accuracy of 92.9% across different readability levels, which outperforms baseline classifiers in terms of classification performance, highlighting the enhancement capabilities of multidimensional linguistic features in CSL readability classification models. This study contributes to the field of CSL education by providing a robust readability classifier as a valuable tool for educators, curriculum designers, and developers of CSL learning materials to ensure appropriate text selection based on learners' proficiency levels.
For a Shimura variety of Hodge type with hyperspecial level structure at a prime
$p$
, Vasiu and Kisin constructed a smooth integral model (namely the integral canonical model) uniquely
determined by ...a certain extension property. We define and study the Ekedahl-Oort stratifications
on the special fibers of those integral canonical models when
$p\,>\,2$
. This generalizes Ekedahl-Oort stratifications defined and studied by Oort on moduli spaces of principally polarized abelian
varieties and those defined and studied by Moonen, Wedhorn, and Viehmann on good reductions of Shimura varieties of PEL type. We show that the Ekedahl-Oort strata are parameterized by certain elements
$w$
in the Weyl group of the reductive group in the Shimura datum. We prove that the stratum corresponding to
$w$
is smooth of dimension
$l\left( w \right)$
(i.e., the length of
$w$
) if it is non-empty. We also determine the closure of each stratum.
PDF
