Land resources are an essential foundation for socioeconomic development. Island land resources are limited, the type changes are particularly frequent, and the environment is fragile. Therefore, ...large-scale, long-term, and high-accuracy land-use classification and spatiotemporal characteristic analysis are of great significance for the sustainable development of islands. Based on the advantages of remote sensing indices and principal component analysis in accurate classification, and taking Zhoushan Archipelago, China, as the study area, in this work long-term satellite remote sensing data were used to perform land-use classification and spatiotemporal characteristic analysis. The classification results showed that the land-use types could be exactly classified, with the overall accuracy and Kappa coefficient greater than 94% and 0.93, respectively. The results of the spatiotemporal characteristic analysis showed that the built-up land and forest land areas increased by 90.00 km2 and 36.83 km2, respectively, while the area of the cropland/grassland decreased by 69.77 km2. The areas of the water bodies, tidal flats, and bare land exhibited slight change trends. The spatial coverage of Zhoushan Island continuously expanded toward the coast, encroaching on nearby sea areas and tidal flats. The cropland/grassland was the most transferred-out area, at up to 108.94 km2, and built-up land was the most transferred-in areas, at up to 73.31 km2. This study provides a data basis and technical support for the scientific management of land resources.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Long-term exposure to microgravity leads to muscle atrophy, which is primarily characterized by a loss of muscle mass and strength and reduces one′s functional capability. A weightlessness-induced ...muscle atrophy model was established using the tail suspension test to evaluate the intervention or therapeutic effect of low-intensity pulsed ultrasound (LIPUS) on muscle atrophy. The rats were divided into five groups at random: the model group (B), the normal control group (NC), the sham-ultrasound control group (SUC), the LIPUS of 50 mW/cm2 radiation group (50 UR), and the LIPUS of 150 mW/cm2 radiation group (150 UR). Body weight, gastrocnemius weight, muscle force, and B-ultrasound images were used to evaluate muscle atrophy status. Results showed that the body weight, gastrocnemius weight, and image entropy of the tail suspension group were significantly lower than those of the control group (p < 0.01), confirming the presence of muscle atrophy. Although the results show that the muscle force and two weights of the rats stimulated by LIPUS are still much smaller than those of the NC group, they are significantly different from those of the pure tail suspension B group (p < 0.01). On day 14, the gastrocnemius forces of the rats exposed to 50 mW/cm2 and 150 mW/cm2 LIPUS were 150% and 165% of those in the B group. The gastrocnemius weights were both 135% of those in the B group. This suggests that ultrasound can, to a certain extent, prevent muscular atrophy.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
The frozen section (FS) diagnoses of pathology experts are used in China to determine whether sentinel lymph nodes of breast cancer have metastasis during operation. Direct implementation of ...a deep neural network (DNN) in clinical practice may be hindered by misdiagnosis of the algorithm, which affects a patient's treatment decision. In this study, we first obtained the prediction result of the commonly used patch-DNN, then we present a relative risk classification and regression tree (RRCART) to identify the misdiagnosed whole-slide images (WSIs) and recommend them to be reviewed by pathologists. Applying this framework to 2362 WSIs of breast cancer lymph node metastasis, test on frozen section results in the mean area under the curve (AUC) reached 0.9851. However, the mean misdiagnosis rate (0.0248), was significantly higher than the pathologists’ misdiagnosis rate (
p
< 0.01). The RRCART distinguished more than 80% of the WSIs as a high-accuracy group with an average accuracy reached to 0.995, but the difference with the pathologists’ performance was not significant (
p
> 0.01). However, the other low-accuracy group included most of the misdiagnoses of DNN models. Our research shows that the misdiagnosis from deep learning model can be further enriched by our method, and that the low-accuracy WSIs must be selected for pathologists to review and the high-accuracy ones may be ready for pathologists to give diagnostic reports.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Trade flows, either measured as gross trade or flows of value-added, tend to be less sensitive to trade barriers in industries that feature a greater share of value-added in its product. Gross trade ...is, in general, more sensitive to trade barriers than the trade in value-added does. The differences between the elasticities of gross trade and value-added trade with respect to distance tend to be smaller for industries with a higher share of value-added in its product.
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BFBNIB, IZUM, KILJ, NUK, PILJ, SAZU, UL, UM, UPUK
Radar-based rainfall estimation is one of the most important inputs for various meteorological applications. Although exciting progresses have been made in this area, accurate real-time rainfall ...estimation is still a significant opening topic that requires practical modeling. The research study presented in this letter improves rainfall estimation accuracy by proposing a random forest and linear chain conditional random-field-based spatiotemporal model (RANLIST). To apply this model for rainfall estimation, the implementing approach is presented. The advantages are listed as follows: 1) RANLIST improves rainfall estimation accuracy by exploiting both underlying local spatial structure of multiple radar reflectivity factors and time-series information of rain processes. 2) The time-series information of rain processes can be utilized in virtue of the presented implementation method. Experiments have been carried out over the radar-covered area of Quanzhou, China, in June and July 2014. Results show that RANLIST is superior to previous works.
Patterns of export shipments Yang, Xuebing
Journal of economic studies (Bradford),
02/2023, Volume:
50, Issue:
2
Journal Article
Peer reviewed
PurposeThis paper studies the frequency and the average size of export shipments at the firm–product–destination level.Design/methodology/approachThis paper sets up a theoretical model about the ...shipping frequency and the shipment size of exports to a given market from individual exporters. Then it confronts the predictions of the model with trade data.FindingsThis paper shows that patterns of export shipments are determined by (1) a product's export potential in a market, which is the exports revenue when the firm delivers the exports of the product to the market in a single shipment in each period; and (2) factors related to the firm's efficiency of managing shipments of the product exported to the market.Originality/valueThis paper reveals some important patterns of export shipments. It provides a theoretical model that explains the patterns.
Economists find that exporters usually have higher markups than non‐exporters. Our work, however, shows that Chinese exporters have lower markups than non‐exporters in China. The result is ...economically and statistically significant. We argue that Chinese exporters have lower markups because they tend to produce products that usually have low markups. The finding is consistent with the hypothesis that China has a comparative advantage in low‐markup products.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, ODKLJ, OILJ, PILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Redundancy elimination techniques are extensively investigated to reduce storage overheads for cloud‐assisted health systems. Deduplication eliminates the redundancy of duplicate blocks by storing ...one physical instance referenced by multiple duplicates. Delta compression is usually regarded as a complementary technique to deduplication to further remove the redundancy of similar blocks, but our observations indicate that this is disobedient when data have sparse duplicate blocks. In addition, there are many overlapped deltas in the resemblance detection process of post‐deduplication delta compression, which hinders the efficiency of delta compression and the index phase of resemblance detection inquires abundant non‐similar blocks, resulting in inefficient system throughput. Therefore, a multi‐feature‐based redundancy elimination scheme, called MFRE, is proposed to solve these problems. The similarity feature and temporal locality feature are excavated to assist redundancy elimination where the similarity feature well expresses the duplicate attribute. Then, similarity‐based dynamic post‐deduplication delta compression and temporal locality‐based dynamic delta compression discover more similar base blocks to minimise overlapped deltas and improve compression ratios. Moreover, the clustering method based on block‐relationship and the feature index strategy based on bloom filters reduce IO overheads and improve system throughput. Experiments demonstrate that the proposed method, compared to the state‐of‐the‐art method, improves the compression ratio and system throughput by 9.68% and 50%, respectively.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In order to conduct a further in-depth exploration of the role of temperature-related parameters in the condition monitoring of wind turbines, this paper proposes a method to assess the condition of ...wind turbines by analyzing the supervisory control and data acquisition system temperature-related parameters based on existing research. A prediction model of time-sequence regression is established, based on the key temperature signals of WTs, so as to reflect their health condition in the form of prediction residuals. A kind of health index from the perspective of temperature-related parameters is developed by separating the statistics concerning the conformity of the predicted values of key temperature parameters within a certain time window from the measured values in order to clearly present the implied information on the health condition of wind turbines contained in the model prediction residuals. The case study shows that the trend of health index from the perspective of temperature-related parameters is consistent with the health condition of wind turbines. In some instances, its decline obviously occurs earlier than the maintenance provided to address the stoppage, suggesting that such indexes can effectively reflect some early health problems of the wind turbines to provide a reference for their scientific maintenance.
The characteristics and mechanism of coupling effects between parallel cladded acoustic waveguides (PCAWs) are essential when considering their applications in acoustic wave control and signal ...processing. We investigated its characteristics and revealed the nature of the coupling effect using a theoretical model of two-dimensional PCAWs and simulation experiments. We derived the eigenmode equation describing the behavior of a single waveguide based on the wave acoustic theory and derived analytic expressions for the coupling effects in the PCAWs using the coupled mode theory. Using the finite-element method, we analyzed the waveguide coupling exhibited by this structure given different configurational and acoustic parameter settings. Both theoretical and simulated results indicate that the input wave directed into one of four ports of this structure propagates and tunnels alternately between the two waveguides. Our theoretical model established yields analytic relations between the coupling lengths as well as the dependence on parameters of the evanescent wave and the structure. Analyses indicate wave coupling in the two PCAWs is essentially mediated by the evanescent wave. The unique evolution of the acoustic wave in PCAWs can be employed to develop pure acoustic devices such as frequency-selective filters, directional couplers, and acoustic switches.
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