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The water resources of the Third Pole (TP), highly sensitive to climate change and glacier melting, significantly impact the water and food security of millions in Asia. However, projecting future spatial‐temporal runoff changes for TP's mountainous basins remains a formidable challenge. Here, we've leveraged the long short‐term memory model (LSTM) to craft a grid‐scale artificial intelligence (AI) model named LSTM‐grid. This model has enabled the production of hydrological projections for the seven major river basins of TP. The LSTM‐grid model integrates monthly precipitation, air temperature, and total glacier mass changes (total_GMC) data at a 0.25‐degree model grid. Training the LSTM‐grid model employed gridded historical monthly runoff and evapotranspiration data sets generated by an observation‐constrained cryosphere‐hydrology model at the headwaters of seven TP river basins during 2000–2017. Our results demonstrate the LSTM grid's effectiveness and usefulness, exhibiting a Nash‐Sutcliffe Efficiency coefficient exceeding 0.92 during the verification periods (2013–2017). Moreover, river basins in the monsoon region exhibited a higher rate of runoff increase compared to those in the westerlies region. Intra‐annual projections indicated notable increases in spring runoff, especially in basins where glacier meltwater significantly contributes to runoff. Additionally, the LSTM‐grid model aptly captures the runoff changes before and after the turning points of glacier melting, highlighting the growing influence of precipitation on runoff after reaching the maximum total_GMC. Therefore, the LSTM‐grid model offers a fresh perspective for understanding the spatiotemporal distribution of water resources in high‐mountain glacial regions by tapping into AI's potential to drive scientific discovery and provide reliable data. Plain Language Summary: Water resources of the Third Pole (TP) significantly impact the water and food security in Asia. However, projecting future spatial‐temporal runoff changes for the TP's mountain basins remains a challenge. Here, we've leveraged the long short‐term memory (LSTM) model to craft a gridded artificial intelligence model (named LSTM‐grid). Trained by the outputs of an observation‐constrained distributed cryosphere‐hydrology model, the LSTM‐grid has enabled reliable spatiotemporal runoff and evapotranspiration projections for the headwaters of seven TP rivers (Yellow, Yangtze, Mekong, Salween, Brahmaputra, Ganges, Indus) till 2100. Our projections show that the river basins in the monsoon region exhibit a higher rate of runoff increase compared to those in the westerlies region. In particular, the proposed approach in this study can reasonably capture the runoff changes before and after the turning points of glacier melting without prior knowledge, highlighting the growing influence of precipitation on runoff after reaching the maximum total glacier mass changes (of a river basin). Hence, the LSTM‐grid model provides a fresh perspective for understanding the spatiotemporal distribution of water resources in high‐mountain glacial regions. Key Points: We use artificial intelligence and an observation‐constrained cryosphere‐hydrology model to project future runoff for seven high‐mountain Third Pole basinsResults show that river basins in the monsoon region exhibited a higher rate of runoff increase compared to those in the westerlies regionThe proposed approach can aptly simulate runoff changes before and after the turning points of glacier melting without prior knowledge [ABSTRACT FROM AUTHOR]

In the context of global warming and the release of projection results from the Coupled Model Intercomparison Project Phase 6 (CMIP6), it is important to conduct research on climate change on the Tibetan Plateau (TP) which exhibits unique geographic characteristics and complex climatic conditions. Using 10 general circulation models (GCMs) from CMIP6 corrected for bias by the daily translation (DT) method, we investigated the projected changes in precipitation and air temperature for the mid‐term (2031–2050) and long‐term (2061–2080) of the 21st century on the TP after evaluating the reliability of the bias correction, for four scenarios based on different combinations of shared socioeconomic pathways and representative concentration pathways. The multimodel ensembles (MMEs) indicated that the projected annual precipitation shows an increasing trend for the mid‐term and long‐term periods, with the projected increase for the long‐term primarily concentrated in areas with less precipitation. Meanwhile, the future precipitation changes exhibit a significant elevation dependency. The rate of increase of precipitation firstly fluctuates and then gradually increases along with the elevation increasing from 1,500 to 5,800 m. The valley value of rate mainly appears in two elevation zones (2,200–2,600 m and 3,400–3,800 m). The projected temporal changes in annual air temperatures reveal obvious warming over the TP. The projected warming is overall more pronounced with increase in elevation; however, it reaches a peak at approximately 5,000–5,200 m and then slows down slightly, indicating that warming is not dependent on elevation in the higher elevation zones. The present results have important implications for investigating the impacts of climate change on the water cycle in alpine regions. [ABSTRACT FROM AUTHOR]

A low‐power consuming amplitude‐shift keying (ASK) modulator designed in 130 nm CMOS technology and operating at 10.5 GHz frequency is presented in this work. The modulator is based on current‐reuse voltage‐controlled oscillator (VCO) which uses the effects of adaptive body‐biasing and injection locking (IL) to achieve low‐phase noise and low‐power operation. The VCO has a phase noise of −106 dBc/Hz at 1 MHz offset. The ASK modulator consumes 790 μW with a 1.1 V voltage supply and draws an average current of 719 μA. For applying the bulk‐biasing signal, a deep n‐well NMOS is used in the PMOS‐NMOS oscillator pair which isolates the substrate and avoids the current path through it. The post‐layout simulation results of the 0.5 × 0.5 mm2 modulator IC verify its low‐power, low‐phase noise operation. It is intended for use in self‐powered active high data rate radio‐frequency identification (RFID) tags. [ABSTRACT FROM AUTHOR]

Accelerating the construction of ecological civilization in the industrial field and guiding the transformation of industry toward a green direction have become a national development strategy. Promoting the coordinated development of energy‐intensive industries such as steel, cement, and power is a key breakthrough in achieving the green transformation of various industries. This study has designed a steel–cement–power polygeneration system with the collaborative utilization of solid waste resources as the ecological link point. Four scenarios, including business‐as‐usual, optimization of product structure, low‐carbon technology application, and policy advancement (PAD), were established to assess the overall energy‐saving and emissions reduction potential of the steel–cement–power polygeneration system from 2015 to 2050. The results show that product structure adjustment and industrial symbiosis have a significant impact on energy saving and emission reduction of key industries. In 2050, the total energy consumption and carbon emissions of the polygeneration system could reach 38,697.64 PJ and 3766.73 Mt CO2. Based on the scenario analysis, the production and use of solid waste in the polygeneration system and the economic benefits are also discussed. Under the PAD scenario, by 2050, the proportion of fly ash as cement raw material will increase to 41%, while the supply of blast furnace slag may be insufficient, and the comprehensive utilization of solid waste can bring economic benefits of 238.32 billion Yuan to the system. [ABSTRACT FROM AUTHOR]

A single‐layer reflective metasurface is proposed in this study to generate dual‐mode dual‐polarized high‐order Bessel vortex beams with equal divergence angle in Ka‐band. The metasurface consists of two different subwavelength elements with different polarisations, which are located in the inner disk region and the outer ring region respectively. The inner element, composed of a square ring and a regular octagon, is proposed to achieve a phase response of 360°. The outer element, which consists of a microstrip line and a double W‐shaped line, is designed to achieve the phase compensation and polarization conversion simultaneously. Equal divergence angle of different orbital angular momentum (OAM) modes is achieved by theoretically calculating the radii of the inner and outer regions. The metasurface prototype is fabricated and tested at 29 GHz, and the results show that the high‐order Bessel beams with +1 mode of x‐polarization and +2 mode of y‐polarization are successfully generated. This work provides a simple and practical method to generate dual‐mode dual‐polarized high‐order Bessel vortex beams for high‐capacity OAM communications. [ABSTRACT FROM AUTHOR]

Summary: A novel wideband bulk acoustic wave (BAW) coupled resonator filter (CRF) combined with external lumped inductors and capacitors is proposed. The filter synthesis method based on the Butterworth–van Dyke (BVD) model of CRF (CRF‐BVD) is also presented. To improve the synthesis accuracy, the CRF‐BVD model is modified and the CRF configuration with a single rather than the traditional multiple coupling layer is adopted in this paper. By establishing equivalence relationships between the modified CRF‐BVD model and the filter prototype synthesis network, exact CRF dimensions are solved through a set of equations without any further parameters tuning. The proposed method exhibits a maximum 37.4% (FBW) for a Chebyshev filter with 9.4‐dB return loss, which overcomes the narrowband limitation of regular BAW filters with FBW below 5%. To demonstrate the synthesis procedure, an n77 band filter with 3.723‐GHz center frequency and 24.2% FBW is designed and simulated. Good agreements are obtained among the simulation results of the prototype synthesis network, the modified CRF‐BVD model, and the co‐simulations of physical model based on the finite element method (FEM) and the CMOS 130‐nm technology. [ABSTRACT FROM AUTHOR]

A low power consumption Amplitude Shift Keying (ASK) modulator employing current reuse cross‐coupled (CRC) LC‐VCO topology and direct injection locking (IL) technique at 10.5‐GHz frequency is presented in this paper. The modulator consumes 864 μW with a DC supply of 1.2 V drawing an average current of 720 μA. The differential VCO is composed of a PMOS‐NMOS pair in stacked series cross‐coupled connection enabling current reuse which results in reduction of the average current drawn from the power source. For comparison, the ASK modulator is also realized with conventional cross‐coupled (CC) topology using NMOS pair. Both circuit approaches are carried out in GF 130‐nm CMOS technology and the post‐layout simulation results of 0.5 × 0.5 mm2 integrated circuits (ICs) show that the CRC topology consumes less power and half of the average current compared to CC topology. Owing to low power requirements, the CRC ASK modulator can be used in self‐powered active Radio Frequency Identification (RFID) tag transmitters for higher data rates. [ABSTRACT FROM AUTHOR]

To improve both thermal stability and friction durability of flexible electronic films with nano‐Ag, a series of flexible films with dendric nano‐Ag embedded into high thermally stable 2‐adamantane containing poly(aryl ether ketone) (2‐ADMPEK, PAEK) substrates are prepared in this work. These films are named as PAEK‐dnAg. The dendric nanostructure of Ag conductive layer performs excellent conductivity with sheet resistance as low as 0.3959 Ω ◻−1. The wide‐angle X‐ray diffraction and scanning electron microscope (SEM) results show dendric nano‐Ag layer well incorporated to PAEK substrates. The results of thermal stability, hydrolysis–oxidation test, adhesion test, and friction durability indicate the PAEK substrate can effectively protect dendric nanosilver conductive layer from heat, harsh oxidation, and friction. The SEM images further show the dendric embedded structure can remain almost unchanged after high temperature (400 °C) heating in air, water boiling oxidation for 12 h, 2500‐cycle 3M tape peeling test, and harsh friction with sanding paper under 5 N, which should lead to the excellent durability of PAEK‐dnAg samples in harsh condition. Thus, PAEK‐dnAgs may show great potential in flexible electronic films application for harsh condition such as high temperature, hydrothermal environment or high friction. [ABSTRACT FROM AUTHOR]

A pole‐converging X‐band low‐noise amplifier (LNA) using 130 nm CMOS technology is proposed. An on‐chip pole‐converging capacitor CPC is added between the gate and drain node of the common‐gate (CG) stage. The capacitor CPC combines with a noise‐reducing inductor L1 to converge poles into the desired band, which results in a pole‐converging effect and wideband performance. The proposed modified broadband simultaneous noise and input‐matching technique is adopted in triple‐cascode configuration to realize good input matching and a low noise figure (NF). Measurement results exhibit a flat maximum power gain of 17.6 dB from 8 to 12 GHz and a reverse isolation over 60 dB within the desired bandwidth along with an NF ranging from 1.5 to 3.6 dB. The LNA core dissipates 17 mW from 2.4 V supply, and the chip size occupies 1.1 × 0.9 mm2 including all pads. The simulated and measured results show good agreement from 8 to 12 GHz. [ABSTRACT FROM AUTHOR]

Thermoplastic polyamide elastomers (TPAEs) were synthesized using polyamide 6 (PA6) as hard segments and polyethylene glycol (PEG) as soft segments. The prepared TPAEs showed a superior mechanical property and thermal property, which the strength and elongation‐at‐break reached 35.50 ± 3.54 MPa and (316.05 ± 20.58)%, respectively, when the molecular weight of soft segment was 600. Furthermore, crystallization property and microphase separation of TPAEs were also investigated in detail, having a significant influence on the foaming behavior of the obtain elastomers. Owing to the restriction of crystalline hard segments, only a few cells formed in the amorphous soft segment regions at foaming temperature of 140°C, while it transformed to larger cells with a thin cell wall at foaming temperature of 160°C and above. When the molecular weight of soft segment increased from 300 to 1000, the average cell size of the foamed TPAEs at 160°C enlarged from 28.73 to 42.17 μm, while the cell density decreased from 5.26 × 108 #/cm3 to 4.25 × 108 #/cm3, both expansion ratio and shrinkage ratio increased gradually. [ABSTRACT FROM AUTHOR]

The authors propose a 4 × 4 circularly polarized (CP) antenna array with wide impedance bandwidth and axial‐ratio (AR) bandwidth and design the same for 60‐GHz applications. The overall structure of the proposed antenna array consists of a cavity‐back circular patch array and two layer feed‐networks. The upper feed‐network is with four TE340 high‐order mode substrate integrated cavities (SIC). Fed with SIC, circular patches with a pair of 42°‐inclined slits can achieve circular polarization. In order to improve the AR bandwidth and gain performance, the substrate integrated waveguide (SIW) sequential rotation feeding technique is utilized in the lower feed‐network. For proof of concept, the 4 × 4 array is fabricated and measured. Measured results show that −10‐dB impedance bandwidth of the proposed antenna array is 27.2% from 52 to 68.4 GHz and 3‐dB AR bandwidth is 18.9% from 55.7 to 67.3 GHz. Furthermore, the 3‐dB gain bandwidth is 26.2% from 53 to 69 GHz with a peak gain reaching 19.3 dBic at 62 GHz. [ABSTRACT FROM AUTHOR]

General circulation models (GCMs) are indispensable for climate change adaptive study over the Tibetan Plateau (TP), which is the potential trigger and amplifier in global climate fluctuations. With the release of Coupled Model Intercomparison Project Phase 6 (CMIP6), 24 GCMs from CMIP5 and CMIP6 were comparatively evaluated for precipitation and air temperature simulations based on the China Meteorological Forcing Dataset (CMFD). Rank score results showed that CMIP6 models generally performed better than CMIP5 for precipitation and surface air temperature over the TP. According to multimodel ensembles (MMEs) of the optimal GCMs for each climate variable, the overestimation of precipitation was both present in CMIP5 and CMIP6, but the results of CMIP6 MMEs were relatively lower in the mid‐west and northern edge of the TP. Furthermore, CMIP6 offered a better performance of precipitation in summer and autumn. For temperature, CMIP6 MMEs were able to reduce the relatively large cold bias that appeared in CMIP5 MMEs in northwest areas to about 1°C and had a smaller bias in spring and winter. Moreover, the investigation into the simulation effects of precipitation at different elevation zones demonstrated that the improved ability of CMIP6 MMEs to reduce bias was mainly concentrated in the elevation zones of 2,000–3,000 m and over 5,000 m, where the precipitation bias was more than 200%. Additionally, CMIP6 MMEs of temperature were able to reduce the bias to less than 2°C in each elevation zone, with the minimum bias of −0.22°C distributed in the region with altitudes from 3,000 to 4,000 m, while the biases of CMIP5 MMEs in the region of 4,000–5,000 m and over 5,000 m were smaller than those of CMIP6 MMEs. Findings obtained in this study could provide a scientific reference for related climate change research over the TP. GCMs of CMIP6 perform better than those of CMIP5 for precipitation and temperature over the TP. Multimodel ensembles (MMEs) of CMIP6 effectively reduce the overestimation of precipitation from CMIP5 MMEs by 40 mm at the annual scale. Improved ability of CMIP6 MMEs shows a significant elevation dependency, especially in elevation zones of 2,000–3,000 m and over 5,000 m for precipitation. [ABSTRACT FROM AUTHOR]

Climate variability and underlying surface changes are strongly associated with runoff alterations. The Yarlung Zangbo River Basin (YZRB) is a typical alpine region located in the southeast Qinghai–Tibet Plateau, where runoff is particularly sensitive and vulnerable to climate and environmental changes. Here, we conducted a quantitative assessment of the contributions of climate variability and underlying surface changes to runoff alterations from 1966 to 2015 in the upper, middle, and lower regions of the YZRB. The year 1997 was identified as the runoff breakpoint in all three sub‐regions, which divided the runoff time series into the baseline period (1966–1997) and change period (1998–2015). An adjusted Budyko framework accounting for glacier runoff was developed to conduct a runoff alteration attribution analysis. The results indicated that the increase in runoff in the upper region was dominated by changes in the underlying surface and glacier runoff, whose contribution accounted for 59.61 and 49.18%, respectively. The runoff increase in the middle and lower regions was mainly attributed to the increase in precipitation, accounting for 39.36 and 129.21% of the total runoff alteration, respectively. Moreover, due to the little variation in vegetation and degradation of permafrost in the upper region, increases in runoff might be largely attributed to increases in subsurface runoff caused by the melting of permafrost. In the middle region, in addition to increased precipitation, vegetation degradation had positive effects on runoff increases. The lower region exhibited far higher water consumption rates due to its extensive and dense vegetation coverage accompanied by rising temperature, which resulted in a negative contribution (−58.74%) to runoff alteration. Our findings may therefore have important implications for water resource security and sustainable development in alpine regions. [ABSTRACT FROM AUTHOR]

Understanding the terrestrial water storage changes (∆S) across global arid and humid river basins is crucial to closing the basin‐scale water balance, but still largely unclear. Here, we combine the Gravity Recovery and Climate Experiment, Global Land Data Assimilation System, and WaterGAP Global Hydrology Model products to study ∆S in 197 global river basins with different aridity by using detrended analyses, and find that annual or multiyear mean ∆S is small in most arid basins but relatively larger in humid basins, given the climate change and anthropogenic impacts removed. Through component analysis, we find that the soil moisture changes in drier basins contribute more to ∆S than those in humid basins; and the contribution of groundwater storage changes to ΔS is irrelevant to varying moisture conditions. Our results will benefit water balance studies in global river basins (e.g., global evapotranspiration estimation with a water balance approach), and have implications for water cycle studies in the context of global change. Plain Language Summary: Terrestrial water storage changes in humid and arid river basins are poorly understood, but have important ecological and socioeconomic impacts. Here, we combine the Gravity Recovery and Climate Experiment, Global Land Data Assimilation System, and WaterGAP Global Hydrology Model products, which are primarily based on satellite remote sensing, to study water storage changes in 197 arid and humid basins distributed across the world. We show that water storage changes on annual or multiyear time scales are negligible in most arid basins but are not negligible in humid basins. Changes in soil moisture contribute more strongly to total water storage change in drier basins than in humid basins, due to the different soil characteristics in drier regions. Our results will benefit water balance studies in global river basins, and have implications for water cycle studies in the context of global change. Key Points: Change in terrestrial water storage (TWS) remains tiny on annual and multiyear time scales, with little fluctuation, in the arid basinsChange in soil moisture makes a significantly greater contribution to change in TWS in arid basinsThe contribution of change in groundwater to change in TWS is independent of varying moisture conditions [ABSTRACT FROM AUTHOR]

Frozen soil undergoing freeze‐thaw cycles has effects on local hydrology, ecosystems, and engineering infrastructure by global warming. It is important to clarify the hydrological processes of frozen soil, especially permafrost. In this study, the performance of a distributed cryosphere‐hydrology model (WEB‐DHM, Water and Energy Budget‐based Distributed Hydrological Model) was significantly improved by the addition of enthalpy‐based permafrost physics. First, we formulated the water phase change in the unconfined aquifer and its exchanges of water and heat with the upper soil layers, with enthalpy adopted as a prognostic variable instead of soil temperature in the energy balance equation to avoid instability when calculating water phase changes. Second, more reasonable initial conditions for the bottom soil layer (overlying the unconfined aquifer) were considered. The improved model (hereinafter WEB‐DHM‐pf) was carefully evaluated at three sites with seasonally frozen ground and one permafrost site over the Qinghai‐Tibetan Plateau ("the Third Pole"), to demonstrate the capability of predicting the internal processes of frozen soil at the point scale, particularly the "zero‐curtain" phenomenon in permafrost. Four different experiments were conducted to assess the impacts of augmentation of single model improvement on simulating soil water/ice and temperature dynamics in frozen soil. Finally, the WEB‐DHM‐pf was demonstrated to be capable of accurately reproducing the zero curtain, detecting long‐term changes in frozen soil at the point scale, and discriminating basin‐wide permafrost from seasonally frozen ground in a basin at the headwaters of the Yellow River. Key Points: A distributed cryosphere‐hydrology model has been significantly improved with the addition of enthalpy‐based permafrost physicsWe include water phase changes in the unconfined aquifer, as well as water and heat exchanges with the upper soil layersThe model accurately reproduces soil water and temperatures at permafrost and seasonally frozen ground sites of upper Yellow River Basin [ABSTRACT FROM AUTHOR]

With the increasing pressure from population growth and economic development, northern China (NC) faces a grand challenge of water scarcity, which can be further exacerbated by climatic and societal changes. The South‐to‐North Water Diversion (SNWD) project is designed to mitigate the water scarcity in NC. However, few studies have quantified the impact of the SNWD on water scarcity within the context of climatic and societal changes and its potential effects on economic and agricultural food in the region. We used water supply stress index (WaSSI) to quantify water scarcity within the context of environmental change in NC and developed a method to estimate the economic and agricultural impacts of the SNWD. Focuses were put on alleviating the water supply shortage and economic and agricultural benefits for the water‐receiving NC. We find that societal changes, especially economic growth, are the major contributors to water scarcity in NC during 2009–2099. To completely mitigate the water scarcity of NC, at least an additional water supply of 13 billion m3/year (comparable to the annual diversion water by SNWD Central Route) will be necessary. Although SNWD alone cannot provide the full solution to NC's water shortage in next few decades, it can significantly alleviate the water supply stress in NC (particularly Beijing), considerably increasing the agricultural production (more than 115 Tcal/year) and bringing economic benefits (more than 51 billion RMB/year) through supplying industrial and domestic water use. Additionally, the transfer project could have impacts on the ecological environment in the exporting regions. Key Points: Societal changes, especially economic growth, are the major contributors to water scarcity problem in northern China (NC) during 2009–2099Diverting water from Yangtze River can significantly reduce water scarcity in NC but cannot entirely solve the issue in next few decadesWater diversion can increase agricultural food (115 Tcal/year) and economic benefit (51 billion RMB/year) in NC under global warming of 1.5°C [ABSTRACT FROM AUTHOR]

The authors propose a 4 × 4 circularly polarized (CP) antenna array with wide impedance bandwidth and axial‐ratio (AR) bandwidth and design the same for 60‐GHz applications. The overall structure of the proposed antenna array consists of a cavity‐back circular patch array and two layer feed‐networks. The upper feed‐network is with four TE340 high‐order mode substrate integrated cavities (SIC). Fed with SIC, circular patches with a pair of 42°‐inclined slits can achieve circular polarization. In order to improve the AR bandwidth and gain performance, the substrate integrated waveguide (SIW) sequential rotation feeding technique is utilized in the lower feed‐network. For proof of concept, the 4 × 4 array is fabricated and measured. Measured results show that −10‐dB impedance bandwidth of the proposed antenna array is 27.2% from 52 to 68.4 GHz and 3‐dB AR bandwidth is 18.9% from 55.7 to 67.3 GHz. Furthermore, the 3‐dB gain bandwidth is 26.2% from 53 to 69 GHz with a peak gain reaching 19.3 dBic at 62 GHz. [ABSTRACT FROM AUTHOR]

A wideband bandpass filter (BPF) based on two dual‐mode stub‐loaded stepped‐impedance resonators (SLSIRs) with mixed electric and magnetic coupling (MEMC) is proposed. Magnetic coupling is realized by using a transmission line, open end‐coupling and inter‐digital‐coupling provide a weak and a strong electric coupling, respectively. Due to the canceling effect of MEMCs, together with its harmonic effect, four transmission zeros (TZs) aside the passband are created and the selectivity of the filter is therefore highly improved. To verify the proposed design, a four‐pole wideband BPF operating at 3.35 GHz with 3 dB fractional bandwidth (FBW) of 32.96% is designed, fabricated, and measured. The measured minimum insertion loss is 0.95 dB, and the passband return loss is better than 11 dB. [ABSTRACT FROM AUTHOR]

A novel ultra‐wideband (UWB) bandpass filter (BPF) with a very compact size and improved out‐of‐band performance is proposed in this letter. The main circuit structure is a composite right‐/left‐handed transmission line unit cell, which has UWB bandpass characteristic as well as compact size. Moreover, two anticoupled line structures added at both ends of the unit cell can produce a new resonant mode and three transmission zeros, so the passband response and upper stopband performance can be improved. The proposed filter is implemented and measured, which shows its 3 dB passband ranges from 3.3 to 10.9 GHz with a fractional bandwidth of 110.9%. Its insertion loss is about 0.6 dB at the centre frequency, while the return loss is better than 13 dB. In addition, the measured results also show the proposed filter has a wide stopband from 11.4 to 30 GHz, whose rejection level is greater than 18 dB. The size of the filter is only 7.4 × 6.4 mm, equal to 0.22 × 0.20 λg. Both the simulated and measured results are in good agreement. [ABSTRACT FROM AUTHOR]

Cryosphere plays an important role in cold‐region (e.g., Tibetan Plateau) hydrological processes under climate change, and thus cryosphere physics should be carefully represented in the hydrological modeling. In this study, based on the Water and Energy Budget‐based Distributed Hydrological Model (WEB‐DHM), we have further improved the cold‐region hydrological processes, by incorporating the enthalpy‐based coupled snow and frozen ground physics (hereinafter WEB‐DHM‐SF), and comprehensively evaluated at the upper Yangtze River Basin under widespread snow cover and frozen ground. The model was calibrated and validated at the basin scale using observed discharge at Zhimenda station during 1981–2016 and simulated discharge with high accuracies. The model also successfully reproduced the basin‐wide daytime and nighttime land surface temperature (LST) as well as snow depth in basin‐averaged time series and spatial distributions. At the point scale, the model successfully reproduced soil moisture and temperature profiles at Tuotuohe based on available yearlong observations. Furthermore, experiments were designed to investigate model improvements and indicated that the incorporation of the three‐layer snow scheme with correct consideration of incident solar radiation attenuation among snow layers resulted in lowered snow melting and reduced discharges. Additionally, the incorporation of frozen ground physics with a correct description of soil water phase changes rendered the modeled soil moistures and temperatures more accurate in the cold season. Through rigorous evaluations of model performance, the incorporation of coupled snow and frozen ground physics demonstrates significant promise for improving cryosphere hydrological simulations in river basins on the TP. Key Points: We incorporated enthalpy‐based coupled snow and frozen ground physics in a distributed biosphere hydrological modelWe rigorously evaluated the model with multiple variables at both the point scale and basin scale of the TP (the upper Yangtze River Basin)Snow and frozen ground physics improves cryosphere hydrology by considering three‐layer snow physics and soil water phase changes [ABSTRACT FROM AUTHOR]

In this article, a broadband beam scanning antenna array is proposed in Q‐band attributed to miniaturized size, wideband and high integration. A patch antenna element is utilized with a back cavity, which is formed by metallic via holes and ground plane. A 1 × 4 series fed sub‐array is implemented by the patch element using multilayer PCB. Four symmetrical sub‐arrays and Butler matrix feeding network are used to form the antenna array with high gain and decrease side lobes. The Butler matrix is implemented by substrate integrated coaxial line, which provides low loss of around 0.09 dB/mm from 40 to 50 GHz. The measured antenna array bandwidth is 9.8 GHz (21.8%) under the condition of voltage standing wave ratio less than 2. The main beam of the antenna array in azimuth direction is tilted to −28.5°, −14.1°, 18.4° and 35.6° and the gains are 13.11, 13.88, 14.02 and 11.78 dBi at 45 GHz, respectively. Both the measured and simulated results agree well. [ABSTRACT FROM AUTHOR]

Groundwater (GW) and recharge as the main drivers of the water budget are challenging to quantify due to the complexity of hydrological processes and limited observations. Understanding these processes in relation to climate is crucial for evaluating future water availability of Tibetan Plateau. By computing storage changes in Gravity Recovery and Climate Experiment terrestrial water storage and Global Land Surface Data Assimilation System land surface state variables and water balance approach, we calculated GW storage changes and recharges. In the Qaidam Basin (northern Tibetan Plateau), terrestrial water storage from the Gravity Recovery and Climate Experiment revealed a significant increasing trend of 25.5 mm/year during 2002–2012. However, an obviously turning point was found around 2012 and terrestrial water storage revealed a significant decreasing rate of 37.9 mm/year during 2013–2016. Similarly, GW (recharge) had a significant increasing trend of 21.2 (4.5) mm/year before 2012 and a decreasing rate of 32.1 (10.9) mm/year after 2012. Domain‐averaged difference (P‐ET) between precipitation (P) and evapotranspiration (ET) also exhibited an increasing trend of 4.4 mm/year during 2002–2012 and a decreasing rate of 9.0 mm/year during 2013–2016. Precipitation followed dissimilar pattern with an increasing rate of 5.3 mm/year during 2002–2012 while no significant trend during 2013–2016. However, ET had a consistent increasing trend over the basin during the past 15 years (0.9 mm/year before 2012 and 9.0 mm/year thereafter). This study concluded that GW amount and distribution is mainly controlled by precipitation and ET. Decrease in precipitation at high elevations and increase in ET may impact future groundwater availability in this region. Key Points: We provide new insights into the groundwater dynamics of Qaidam Basin (TP), the poorly monitored aquifers in relation to climatePrecipitation and ET are the major controllers of TWS and GW distribution in this regionTemporal variations in precipitation and ET explain the groundwater, recharge, and TWS variations in the basin [ABSTRACT FROM AUTHOR]

Ambient nutrient changes influence the coupling of nitrogen (N) and phosphorus (P) in terrestrial ecosystems, but whether it could alter the scaling relationship of plant leaf N to P concentrations remains unclear.Here, we conducted experimental manipulations using Arabidopsis thaliana, with five levels of N and P additions and nine repeated experiments, and then evaluated the changes in the scaling relationship of leaf N to P concentrations under nutrient additions.Overall, leaf N concentration scaled as 0.552 power of leaf P concentration for all data pooled. However, when considering the effect of the type of nutrient addition, the scaling relationship for pooled data of the five levels of N addition was insignificant at two growth stages (young‐leaf and mature‐leaf stages), whereas the scaling relationship for pooled data of the five levels of P addition was significant with exponents of 0.290 and 0.268 at the two growth stages, respectively. Furthermore, the scaling exponent decreased with the increasing levels of N addition, but increased with the increasing levels of P addition. This suggests that high nutrient availability decreases the variability in its own concentration, but promotes the fluctuation in another tightly associated nutrient concentration in leaves among plant individuals. We call this as Nutrient Availability–Individual Variability Hypothesis.Our results suggest that scaling relationship of leaf N to P concentrations is largely modulated by the type and level of nutrient addition, and analyses of leaf N vs. P scaling relationships using pooled data could lose much information rooted in biologically and ecologically significant variances. These findings provide important implications for the parameterization in modelling stoichiometric growth and nutrient cycles in terrestrial ecosystems, and for understanding population structures, processes and functioning under varying nutrient environments. However, whether our observed patterns in A. thaliana could be extended to those at community level warrants further studies and more validations. A plain language summary is available for this article. Plain Language Summary [ABSTRACT FROM AUTHOR]

In this letter, a novel miniaturized and low insertion loss 60GHz on‐chip bandpass filter (BPF) is presented, which is fabricated by a standard 0.13 μm CMOS process. This BPF is mainly composed of a three‐line coupled structure. The selectivity of the filter is improved by introducing two transmission zeros on both sides of the desired passband because of the source‐load coupled structures. In addition, the gap between the three coupled lines can affect the coupling strength to determine the fractional bandwidth (FBW) of the filter. The miniaturization of the filter is also achieved by folding the coup led line of a quarter wavelength. The overall size of the fabricated BPF chip is 267 μm × 376 μm. The measured results show that the insertion loss and fractional bandwidth of the filter at the center frequency of 60 GHz are −2.03 dB and 47%, respectively. The simulated and measured results are in good agreement. [ABSTRACT FROM AUTHOR]

ABSTRACT: We review recent climate changes over the Tibetan Plateau (TP) and associated responses of cryospheric, biospheric, and hydrological variables. We focused on surface air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, lakes, streamflow, and biological system changes. TP is getting warmer and wetter, and air temperature has increased significantly, particularly since the 1980s. Most significant warming trends have occurred in the northern TP. Slight increases in precipitation have occurred over the entire TP with clear spatial variability. Intensification of surface air temperature is associated with variation in precipitation and decreases in snow cover depth, spatial extent, and persistence. Rising surface temperatures have caused recession of glaciers, permafrost thawing, and thickening of the active layers over the permafrost. Changing temperatures, precipitation, and other climate system components have also affected the TP biological system. In addition, elevation‐dependent changes in air temperature, wind speed, and summer precipitation have occurred in the TP and its surroundings in the past three decades. Before projecting multifaceted interactions and process responses to future climate change, further quantitative analysis and understanding of the change mechanisms is required. [ABSTRACT FROM AUTHOR]

ABSTRACT The Tibetan Plateau ( TP) experienced a rapid warming and wetting in recent decades. The elevation dependence of warming rate has been established, while the question of trend in precipitation against the elevation gradient remains open. By using the in situ observation of precipitation, air temperature, and surface specific humidity from 91 stations over and around the TP, this study investigated how the trends in summer precipitation varied along the elevation gradient over and around the TP during the period 1970-2014. The major findings are as follows: (1) the trends in summer precipitation from 1970 to 2014 displayed an increasing tendency at a rate of 0.83% decade−1 km−1 with the increased elevation, and the rate for 1991-2014 (2.23% decade−1 km−1) is even greater and (2) the temporal trends in surface air temperature, surface specific humidity (surface water vapour) from in situ observations and total column of water vapour from Japanese 55-year reanalysis ( JRA-55) data over most stations consistently display similar elevation dependence, which provides a plausible explanation for the elevation dependence of the summer precipitation trends based on the Clausius-Clapeyron relationship. The large-scale atmospheric circulations are other possible factors influencing the elevation dependence of summer precipitation trends, which needs further investigations. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a dual-band LC voltage switched oscillator (VCO), which can be regulated between 3.6-4.5 GHz and 6.5-7.8 GHz frequency bands. The VCO is realized employing a tunable LC tank with switched capacitors, which makes the dual-band operation available. The VCO has been implemented in 0.13 μm SiGe BiCMOS technology, and draws around 5 mA and 5.2 mA in the core circuit with a 1.6 V supply at 4.22 GHz and 7.3 GHz, respectively. The measured phase noise performance of the VCO are −103.36 dBc/Hz for 4.22 GHz and −104.69 dBc/Hz for 7.3 GHz at 3 MHz offset. The core area of the chip is 0.13 mm2 based on the use of a symmetric inductor. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1439-1441, 2017 [ABSTRACT FROM AUTHOR]

Snow and frozen soil are important factors that influence terrestrial water and energy balances through snowpack accumulation and melt and soil freeze-thaw. In this study, a new land surface model (LSM) with coupled snow and frozen soil physics was developed based on a hydrologically improved LSM (HydroSiB2). First, an energy-balance-based three-layer snow model was incorporated into HydroSiB2 (hereafter HydroSiB2-S) to provide an improved description of the internal processes of the snow pack. Second, a universal and simplified soil model was coupled with HydroSiB2-S to depict soil water freezing and thawing (hereafter HydroSiB2-SF). In order to avoid the instability caused by the uncertainty in estimating water phase changes, enthalpy was adopted as a prognostic variable instead of snow/soil temperature in the energy balance equation of the snow/frozen soil module. The newly developed models were then carefully evaluated at two typical sites of the Tibetan Plateau (TP) (one snow covered and the other snow free, both with underlying frozen soil). At the snow-covered site in northeastern TP (DY), HydroSiB2-SF demonstrated significant improvements over HydroSiB2-F (same as HydroSiB2-SF but using the original single-layer snow module of HydroSiB2), showing the importance of snow internal processes in three-layer snow parameterization. At the snow-free site in southwestern TP (Ngari), HydroSiB2-SF reasonably simulated soil water phase changes while HydroSiB2-S did not, indicating the crucial role of frozen soil parameterization in depicting the soil thermal and water dynamics. Finally, HydroSiB2-SF proved to be capable of simulating upward moisture fluxes toward the freezing front from the underlying soil layers in winter. [ABSTRACT FROM AUTHOR]

ABSTRACT The Tibetan Plateau ( TP) affects its surroundings significantly through thermal and dynamic processes. Reductions in near-surface wind speed ( Ws) have been observed from ground measurements but how the trends of Ws vary with the elevation is less clear. Trends of Ws with respect to elevation were investigated using long-term daily records taken from 1970 to 2012 of Ws and maximum ( Tmax), minimum ( Tmin), and mean ( Tmean) air temperatures from 139 stations over and around the TP. The major findings are as follows. (1) Pronounced reductions in Ws can be observed in all seasons and annually across the TP. Spring demonstrates the most prominent weakening. The rate of reductions in Ws was amplified with elevation, and higher-elevation environments experienced greater changes in Ws than lower-elevation areas. Elevation-dependent reductions in Ws have intensified from 1970 to 2012. (2) Statistically significant negative correlations between Ws and corresponding near-surface temperatures were detected. We suggested that the elevation-dependent warming and thereby the increased surface roughness at higher-elevation environments may contribute to the elevation-dependent reductions in Ws over and around the TP. More detailed mechanisms causing this pattern are to be further explored. [ABSTRACT FROM AUTHOR]

ABSTRACT This article proposes a 3-5 GHz IR-UWB (impulse radio ultra-wide band) impulse generator. The impulse generator is mainly composed of an ultra-narrow pulse generator and an on-chip filter. The IR-UWB impulse generator is implemented in 0.13 μm CMOS, while the chip size is 0.29 mm2. The peak-to-peak voltage of the output signals is 600 mV. When the data rate is 10 MHz, the circuit consumes 6.95 mW. The impulse generated can fulfill the FCC spectral mask for indoor UWB systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2242-2245, 2016 [ABSTRACT FROM AUTHOR]

This study presents a two‐dimensional (2D) scanning antenna array of ultra high frequency radio frequency identification system with high stability and reliability in metal cavity. The antenna array is composed of nine elements and a feeding network. The two‐shorting‐plate planar inverted‐F antenna is designed as antenna element with small dimension 10 × 10 × 1.5 cm3. The bandwidth of element is about 72 MHz (840–912 MHz) under the condition of voltage standing wave ratio (VSWR) <2. The feeding network consists of a butler matrix and three three‐way power dividers. Both the nine antenna elements and a feeding network are specified within 33 × 30 × 20 cm3 areas, where switches are used to change the connection of feeding network to obtain 2D scanning beam. The measured bandwidth is about 30 MHz (845–875 MHz) under the condition of VSWR <2, which covers Europe standard (865–868 MHz) completely. The scanning beam directions are ±60° with 10 dBi gain at the xz‐plane and ±50° with 10 dBi gain at the yz‐plane. The read rate of the proposed antenna array achieves 100% in the metal cavity with 18 dBm input power. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates when the brand is promoting a specific social role (as a friend or as a leader), whether the physical position of a brand image in relation to the customer's image influences brand evaluations. Two studies reveal that the match between the promoted social role and the visual representations of the brand and customer in the ad layout improves evaluations. When the brand is promoted as a friend to its customers, consumers evaluate it more positively if the image of the brand is located horizontally and near to the image of the customer. However, when the brand is promoted as a leader to its customers, consumers evaluate it more positively if the image of the brand is located above and far from the image of the customer. [Copyright &y& Elsevier]

In this article, an approach to miniaturize bandpass filter with half-wavelength resonators is proposed.Theoretical analysis shows that the passband of the filter can be shifted to lower frequency by shunt open stubs. Furthermore, to prove its practical viability, three miniaturized bandpass filters with T-shape, comb-shape, and interdigital-like shunt open stubs are designed, fabricated, and compared. The filter with interdigital-like shunt open stubs has the minimized size 13.3 × 8.5 mm2 and maximum insertion loss around − 1.7 dB. The simulated and measured results agree well. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:890-894, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27465 [ABSTRACT FROM AUTHOR]

A microstrip-based segmented coupling reader antenna is proposed for near-field ultra high frequency radio frequency identification applications. The measured reading distance is 13.5 cm in the air and the measured bandwidth is around 55 MHz (895-950 MHz) under the condition of voltage standing wave ratio less than 2.0, which covers the Federal Communications Commission standard (902-928 MHz) completely. In addition, the simulated far-field gain is around 4.7 dBi. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26144 [ABSTRACT FROM AUTHOR]

The method of structural optimization of the steel manufacturing process is described, and the development logic of layer‐by‐layer progression from the analysis‐optimization of the set of procedures' functions, the analysis‐optimization of the set of procedures' relations, to the reconstruction‐optimization of the set of processes' procedures is explained. Four different simulation models from Kambara Reactor (KR) to continuous casting (CC) are established using Flexsim simulation software. The theory of structural optimization and simulation models complements each other, which promotes the understanding of structural optimization methods and the application of simulation models. The logistics operation of the simulation model under different production conditions is investigated, especially considering the influence of time factors. Finally, the effectiveness of the structural optimization method and the simulation model is verified by comparing the simulation results with the actual production of a steel plant. [ABSTRACT FROM AUTHOR]

The title compound, C12H12BrNO4S2, was obtained by the Sandmeyer reaction from ethyl 3-amino-4-cyano-5-[(2-eth-oxy-2-oxoeth-yl)sulfan-yl]thio-phene-2-carboxyl-ate. The dihedral angle between the thiophene ring and linked CO2 ester group is 2.0 (5)°.