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People often use qualitative relations to describe locations or directional information, especially in written communication, such as 'the restaurant is located at the southeast corner of the square'. However, when a large number of spatial entities are involved, qualitative relations alone are not intuitive enough for people to understand a spatial configuration. In fact, many applications, e.g. pertaining to sharing travel experiences, use sketch maps, i.e. maps focusing on the main features of an area whilst abstracting exact scale measurements, to help demonstrate abstract qualitative relations with more intuitive geometric points. Current approaches for generating point sketch maps from qualitative spatial relations require a high level of expertise, face inherent difficulties with efficiently processing large-scale data in bulk, and are vulnerable to inaccurate or conflicting information contained in qualitative data. To address these limitations, by incorporating machine learning techniques, we propose to translate the problem into an optimization problem of data reconstruction, enabling a novel end-to-end approach for generating point sketch maps from qualitative directional relations in bulk. Experiments on real-world datasets show that the proposed approach has very high accuracy and is robust even with a large portion of inaccurate or incomplete information. [ABSTRACT FROM AUTHOR]

With the explosion of crab farming in China, the urgent need to treat crab wastewater can never be overemphasized. Hence, in this study, excitation–emission matrix (EEM) fluorescence spectroscopy with parallel factor analysis (PARAFAC), moving window two-dimensional correlation spectroscopy (MW-2DCOS) and structural equation modeling (SEM) were employed to identify changes in the dissolved organic matter (DOM) fractions in a crab farming park and reveal latent factors associated with removal processes. Seven components (C1–C7) were extracted from DOMs by EEM-PARAFAC as follows: C1: microbial byproduct-like substances, C2: visible-tryptophan-like substances, C3: fulvic-like substances, C4: phenolic-like substances, C5: ultraviolet tyrosine-like substances, C6: D-tryptophan-like substances and C7: L-tryptophan-like substances. Interestingly, C7 (39.20%), a representative component of DOM in the crab farming pond, was deeply degraded in the aeration pond by aerobic microbes, whereas C6 was absent in the crab pond. According to 2DCOS, the changing order of the components was C7 → C4 → C6 → C5 → C2 → C1 → C3, and the changing order of the functional groups was carboxylic → phenolic → aromatic. As assessed by MW-2DCOS, the Fmax of the components, especially components C2, C5 and C6 (and with the exception of C4 and C7) exponentially increased in the aeration pond, where an accumulative effect occurred. C2, C5 and C7 were removed by 24.26%, 39.42% and 98.25% in the crab farming system, and were deeply degraded in the paddy-field, purification pond and aeration pond, respectively. As assessed by SEM, the latent factors of organic matter removal were C1, C2, C4, C5, SUVA254, CODMn and DO. This study could be conducive to comprehensively characterizing the removal of components and functional groups of DOMs in crab farming parks. [ABSTRACT FROM AUTHOR]

Summary: A frame pin‐supported wall structure (FPWS) is a typical rocking structure that releases constraints at the bottom of the wall. The existing studies have demonstrated that FPWSs can control the structural deformation effectively. A distributed parameter model (DPM), which consists of a flexural beam and a shear beam connected by infinitely rigid links, is used to describe the performance of FPWSs. The flexural and the shear beams represent the wall and the frame, respectively. However, there are several flaws in the DPM. For instance, (1) it is not appropriate to simplify the frame into a shear beam, (2) the infinitely rigid links cannot demonstrate the interaction between the frame and the wall properly, and (3) the stiffness variation along the height of the frame is not considered. In this study, an upgraded parameter model (UPM) was proposed to simulate the FPWS based on the DPM. Specifically, (1) a lumped mass model is employed to simulate the frame instead of the shear beam; (2) the pin‐supported wall (PW) and the frame are connected only at several positions, that is, at the floor levels; and (3) the variation of the stiffness is also considered in the UPM. The results via the UPM were compared with those using DPM and OpenSees model. A parametric analysis was then carried out using the UPM. The results indicated that the proposed UPM can describe the behavior of FPWSs accurately. [ABSTRACT FROM AUTHOR]

Agricultural activities exacerbate nitrogen (N) imbalances in the agroecosystem by disturbing the N inputs and outputs, yet the influence of changes in cropping systems on the N balance of agroecosystems remains unclear. In this study, at the field scale, we calculated the N balance of four cropping systems, (1) traditional crops with traditional crop rotation (G–G), (2) vegetables with traditional crop rotation (V–G), (3) vegetables with vegetable rotation (V–V), and (4) greenhouse vegetables (GHV); then analyzed the influence of changes in cropping systems from 1995 to 2015 on the N balances in the agroecosystems in sub-watersheds of the Dagu River. The results indicate that N balances were higher in GHV, V–V, and V–G than G–G, due to significantly higher inputs of N fertilizers and lower N use efficiency (NUE) in vegetable cultivation compared to traditional crops. Driven by economic benefits between 1995 and 2015, V–G, V–V, and GHV replaced G–G in a considerable number of cultivation areas in the sub-watersheds. These changes resulted in an increase of 109.9–170.1% in the N balance in the agroecosystem in the sub-watersheds between 1995 and 2015. In the entire watershed, the total N surplus contribution by V–V, V–G, and GHV increased from 39.3% to 79.1% between 1995 and 2015. These findings suggest that increased vegetable cultivation contributed to the increased risk of N pollution in agricultural production. Thus, there should be a focus on the management of cropping systems to control N loss from agricultural lands. [ABSTRACT FROM AUTHOR]

The design, materials, process, fabrication, and reliability of a heterogeneous integration of four chips and four capacitors by a fan-out wafer-level packaging (FOWLP) method are investigated in this paper. Emphasis is placed on the application of a new assembly process for fabricating the redistribution layers of the FOWLP. Reliability assessments, such as the thermal cycling and drop test, are also performed. [ABSTRACT FROM AUTHOR]

The design, materials, process, fabrication, and reliability of fan-out wafer-level packaging (FOWLP) with chip-first and die face-up method are investigated in this paper. Emphasis is placed on the issues and their solutions (such as reconstituted carrier, die-attach film placement, pitch compensation, die shift, epoxy molding compound dispensing, compression molding, warpage, and Cu revealing) during the fabrication of a very large test chip (10 mm $\times10$ mm $\times 150\,\,\mu \text{m}$ ) and test package (13.47 mm $\times13.47$ mm), and three redistribution layers with the smallest linewidth/spacing = $5~\mu \text{m}/5~\mu \text{m}$. The FOWLP test package on a six-layer printed circuit board is subjected to 1000 drops of the shock test with a magnitude = 1500 G/ms. Recommendations of process integration and guidelines on FOWLP with chip-first and die face-up are provided. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sub-micron solder thickness Cu/Sn/Cu sandwich structure and Sn/Cu binary samples were studied by reflow and aging, to explore the unique “solder-depletion” phenomenon. [•] The “Cu6Sn5 consumption based” Cu3Sn growth was also studied, and it showed very different growth rate and characteristics. [•] Optimized thickness for ultra-thin solder layer interconnection were studied by experiments. Formation of micro-voids was observed and discussed. [•] Effects of acid cleaning (before electroplating) on the microstructures was also discussed. [Copyright &y& Elsevier]

• The N 2 emission rate was 1.23 ± 0.83 mg N m−2 h−1 in Chaohu Lake. • The upper and lower limits of uptake velocity were 3.33 m yr−1 and 2.67 m yr−1. • The N removal efficiency via denitrogen was around 26.14% in Chaohu Lake. • The total N removal efficiency of the Chaohu lake was 31.45%. • N removal efficiency of reservoirs has a power relationship with water discharge. Lakes and reservoirs are important inland waterscapes in linking nitrogen (N) transport and removal from the terrestrial to marine ecosystems. N removal processes eliminate N permanently from lakes and reservoirs, including denitogen, permanent burial and biomass harvest. The N removal efficiency (R _removal , i.e. the fraction of N removal amount against total N loads to the lake) is an important parameter for the quantification of N removal from lakes and reservoirs. Intrinsically, R _removal depends on hydrologic load and total N uptake velocity (V f_removal). However, it is a challenge in determining V f_removal which can be used to model R _removal of lakes and reservoirs. Furthermore, there is less studies in distinguishing the N uptake velocity of individual processes from each other. Here, we estimated the magnitude of each uptake velocity of N removal processes with field observed data, and further presented an integrated V f_removal to estimate R _removal of a typical eutrophic lake (the Chaohu Lake) in Eastern China. The mean dinitrogen emission rate was 1.23 ± 0.83 mg N m−2 h−1 in Chaohu Lake in 2016. The uptake velocity of denitrogen, permanent N burial and biomass harvest was 2.67 m yr−1, 0.25 m yr−1 and 0.23 m yr−1, respectively. The removal efficiency of denitrogen, permanent N burial and biomass harvest was 26.14%, 2.76% and 2.56%, respectively. The integrated value of V f_removal was 3.33 m yr−1. We finally compiled hydrological data of 566 large reservoirs in Changjiang River network, and modelled the N removal by combining our estimated value of V f_removal with hydrological data. We found a significant power relationship between N removal and the reservoir discharge, which can predict the variation of N removal of each reservoir in Changjiang River network. Our research helps to understand N removal in lakes and reservoirs at an entire river network scale. [ABSTRACT FROM AUTHOR]

Summary: Precast concrete structures are increasingly being adopted by building designers in regions of high seismicity. An unbonded posttensioned (PT) precast split shear wall system (UPPSSW) was proposed by the Precast Seismic Structural Systems (PRESSS). The UPPSSW system is composed of two or more single precast concrete wall panels that are connected together with energy‐dissipating shear connectors and anchored to the foundation with unbonded PT tendons located at the panel center. In this paper, an optimum design program has been developed for designing this system. The objective of the optimum process is to find the optimum combination between PT tendons and shear connectors while keeping the moment capacity of the wall equal to the applied design moment and achieving zero residual drift simultaneously. In addition, MATLAB was employed to explore an optimization program using genetic algorithm. Compared with the existing design methods for the system, the optimum design program proposed in this research is accurate, efficient, and direct. Moreover, it can yield the optimum design automatically and quickly. As a result, the existing lengthy and manual design process of trial and error for the system can be avoided. [ABSTRACT FROM AUTHOR]

Dam reservoirs in headwater catchments, as critical zones for their proximity to terrestrial sources, play important roles in dissolved organic carbon (DOC) cycling. However, the effects of ecosystem metabolism (EM) on DOC cycling are not well known. Here, in-situ diurnal and monthly observations were conducted to measure EM (including gross primary production (GPP), ecosystem respiration (ER) and heterotrophic respiration (HR)), DOC turnover and CO 2 emissions in a headwater catchment reservoir in Southeastern China in 2020. Our study showed the nocturnal CO 2 emission rate was about twice as high as in daytime, and was strongly driven by EM. The values for DOC turnover velocity ranged from 0.10 to 1.59 m/day, and the average DOC turnover rate was 0.13 day−1, with the average removal efficiency of 12%. The contribution of respired DOC to daily CO 2 emissions ranged from 17% to 61%. The accumulated efficiencies were estimated to be 13% for the selected 15 reservoirs throughout the Changjiang River network, corresponding to about 0.34 Tg C/year of the respired DOC. The modified CO 2 flux was 0.75 Tg C/year, and respired DOC accounted for about 45% of total emitted CO 2 from the 15 larger reservoirs. Our research emphasizes the necessity of incorporating the effects of EM into studies of reservoir DOC removal and CO 2 emissions. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Recent studies have indicated an association between sedentary behavior (SB), particularly patterns of SB, and bone health. However, it remains uncertain how different patterns of SB in overweight/obesity older women impact their bone health. This study aimed to investigate the association between objectively measured SB patterns and bone health in Chinese community-dwelling overweight/obesity older women., Methods: Cross-sectional data were obtained from a baseline survey of Physical Activity and Health in Older Women Study. Quantitative ultrasound was used to measure speed of sound (SOS), broadband ultrasound attenuation (BUA), bone quality index (BQI) and T value to evaluate bone health. SB patterns were measured using triaxial accelerometers, including sedentary time in SB bouts of ≥ 10, 30, and 60 min, number of SB bouts ≥ 10, 30, and 60 min. Multiple linear regression was used to examine the associations of different SB patterns with bone health., Results: After adjusting for confounders, sedentary time in SB bouts ≥ 60 min, number of SB bouts ≥ 60 min were significantly associated with bone health, with a lower SOS [β = -2.75, 95% confidence interval (CI): -4.96 to -0.53, P = 0.015], BUA (β = -1.20, 95% CI: -2.14 to -0.26, P = 0.013), BQI (β = -1.56, 95% CI: -2.63 to -0.49, P = 0.004), T value (β = -0.08, 95% CI: -0.14 to -0.03, P = 0.004) per 60 min increase of sedentary time in SB bouts ≥ 60 min, and a lower SOS (β = -3.97, 95% CI: -7.54 to -0.40, P = 0.029), BUA (β = -1.80, 95% CI: -3.44 to -0.16, P = 0.031), BQI (β = -2.28, 95% CI: -4.08 to -0.47, P = 0.014) and T value (β = -0.12, 95% CI: -0.22 to -0.03, P = 0.013) per bout increase of SB bouts ≥ 60 min, respectively., Conclusion: Limiting the duration of prolonged sedentary bouts and minimizing the occurrence of number of SB bouts ≥ 60 min could be essential in bone health management, especially for those older people who are overweight/obesity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 He, Du, Li, Ren, Chen and Pan.)

In recent decades, most lakes in Eastern China have suffered unprecedented nitrogen pollution, making them potential "hotspots" for N 2 O production and emission. Understanding the mechanisms of N 2 O production and quantifying emissions in these lakes is essential for assessing regional and global N 2 O budgets and for mitigating N 2 O emissions. Here, we measure isotopic compositions (δ 15 N-N 2 O and δ 18 O-N 2 O) and site preference (SP) of dissolved N 2 O in an attempt to differentiate the relative contribution of N 2 O production processes in the shallow, eutrophic Chaohu Lake, Eastern China. Our results show that the bulk isotope ratios for δ 15 N-N 2 O, δ 18 O-N 2 O, and SP were 5.8 ± 3.9‰, 29.3 ± 13.4‰, and 18.6 ± 3.2‰, respectively. More than 76.8% of the dissolved N 2 O was produced via microbial processes. Findings suggest that dissolved N 2 O is primarily produced via nitrification (between 27.3% and 48.0%) and denitrification (between 31.9% and 49.5%). In addition, isotopic data exhibit significant N 2 O consumption during denitrification. We estimate the average N 2 O emission rate (27.5 ± 26.0 μg N m -2 h -1 ), which is higher than that from rivers in the Changjiang River network (CRN). We scaled-up the regional N 2 O emission (from 1.98 Gg N yr -1 to 4.58 Gg N yr -1 ) using a N 2 O emission factor (0.51 ± 0.63%) for shallow lakes in the middle and lower region of the CRN. We suggest that beneficial circumstances for promoting complete denitrification may be helpful for reducing N 2 O production and emissions in fresh surface waters., (Copyright © 2019 Elsevier Ltd. All rights reserved.)