mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
A UHF RFID system with on-chip-antenna tag for short range communication

A UHF RF identification system based on the 0.18 μm CMOS process has been developed for short range and harsh size requirement applications, which is composed of a fully integrated tag and a special reader. The whole tag chip with the antenna takes up an area of 0.36 mm~2, which is smaller than other reported tags with an on-chip antenna (OCA) using the standard CMOS process. A self-defined protocol is proposed to reduce the power consumption, and minimize the size of the tag. The specialized SOC reader system consists of the RF transceiver, digital baseband, MCU and host interface. Its power consumption is about 500 mW. Measurement results show that the system's reading range is 2 mm with 20 dBm reader output power. With an inductive antenna printed on a paper substrate around the OCA tag, the reading range can be extended from several centimeters to meters, depending on the shape and size of the inductive antenna.
An energy-efficient and highly linear switching capacitor procedure for SAR ADCs

An energy-efficient and highly linear capacitor switching procedure for successive approximation register (SAR) ADCs is presented. The proposed switching procedure achieves 37% less switching energy when compared to the well-known V_(CM)-based switching scheme. Moreover, the proposed method shows better linearity than the V_(CM)-based one. The proposed switching procedure is applied to a 10-bit 1.0 V 300 kS/s SAR ADC implemented in 0.18 μ m standard CMOS. The measured results show the SAR ADC achieves an SNDR of 55.48 dB, SFDR of 66.98 dB, and consumes 2.13 μ W at a 1.0 V power supply, resulting in a figure-of-merit of 14.66 fJ/conversion-step. The measured peak DNL and INL are 0.52/-0.47 LSB and 0.72/-0.79 LSB, respectively, and the peak INL is observed at 1/4(V_(FS)) and 3/4(V_(FS)), the same as the static nonlinearity model.
Deposition and doping of CdS/CdTe thin film solar cells

1% oxygen is incorporated into both CdS and CdTe layers through RF sputtering of CdS/CdTe thin film solar cells. The optical and electrical parameters of the oxygenated and O_2-free devices are compared after CdCl_2 treatment and annealing in ambient Ar and/or air. The effects of ambient annealing on the electrical and optical properties of the films are investigated using current-voltage characterization, field emission scanning electron microscopy, X-ray diffraction, and optical transmission spectroscopy. The 1% oxygen content can slightly increase the grain size while the crystallinity does not change. Annealing in ambient Ar can increase the transmission rate of the oxygenated devices.
The effect of multi-intermediate bands on the behavior of an InAs_(1-x)N_x/GaAs_(1-y)Sb_y quantum dot solar cell

A mathematical model of quantum dot intermediate band solar cells (QDIBSCs) is investigated using two intermediate bands (IBs). These two IBs arise from the quantum dot (QD) semiconductor material within the bandgap energy. Some parameters such as the width of the QD (W_(QD)) and the barrier thickness or the inter-dot distances between the QDs (B_T) are studied to show their influence on the performance of the QDIBSC. The time-independent Schrodinger equation, which is solved using the Kronig-Penney model, is used to determine the position and bandwidth energies of the two IBs. In our proposed model, the cubic shape of the QDs from InAs_(0.9)N_(0.1) and the barrier or host semiconductor material from GaAs_(0.98)Sb_(0.02) are utilized. It is shown from the results obtained that changing the parameters W_(QD) and B_T has more influence on the bandwidth energy for the first IB, Δ_1, than in the case of the second IB, Δ_2. The optimum power conversion efficiencies (PCEs) of the QDIBSCs with two IBs for the model under study are 58.01% and 73.55% at 1 Sun and maximum solar concentration, respectively. One can observe that, in the case of the two IBs, an improvement of the PCE is achieved.
A multifunctional switched-capacitor programmable gain amplifier for high-definition video analog front-ends

A multifunctional programmable gain amplifier (PGA) that provides gain and offset adjusting abilities for high-definition video analog front-ends (AFE) is presented. With a switched-capacitor structure, the PGA also acts as a sample and holder of the analog-to-digital converter (ADC) in the AFE to reduce the power consumption and chip area of the whole AFE. Furthermore, the PGA converts the single-ended video signal into differential signal for the following ADC to reject common-mode noise and interferences. The 9-bit digital-to-analog converter (DAC) for gain and offset adjusting is embedded into the switched capacitor networks of the PGA. A video AFE integrated circuit based on the proposed PGA is fabricated in a 0.18-μm process. Simulation and measurement results show that the PGA achieves a gain control range of 0.90 to 2.34 and an offset control range of —220 to 220 mV while consuming 10.1 mA from a 1.8 V power supply.
Impact of barrier thickness on gate capacitance——modeling and comparative analysis of GaN based MOSHEMTs

A mathematical model is developed predicting the behavior of gate capacitance with the nanoscale variation of barrier thickness in AlN/GaN MOSHEMT and its effect on gate capacitances of AlInN/GaN and AlGaN/GaN MOSHEMTs through TCAD simulations is compared analytically. AlN/GaN and AlInN/GaN MOSHEMTs have an advantage of a significant decrease in gate capacitance up to 108 fF/μm~2 with an increase in barrier thickness up to 10 nm as compared to conventional AlGaN/GaN MOSHEMT. This decrease in gate capacitance leads to improved RF performance and hence reduced propagation delay.
Voltage assisted control of spin-transfer nano-oscillators

The spin-transfer nano-oscillator (STNO) has recently acquired a huge amount of research interest, due to its promising easy tunability along with the miniature size. The output frequency control of an STNO through magnetic field and current has been examined almost to its full extent; however, there are issues that still need to be addressed. Here, we propose a novel way of voltage control of the output frequency of an STNO, and alongside reducing its power requirement.
高血压心脏重构

21世纪中国成人高血压患病率已达30%,是临床心力衰竭发生的主要危险因素。据我国部分地区42家医院对10 714例心力衰竭住院病历回顾性调查发现,1980-2000年心力衰竭病因中高血压占比从8.0%升至12.9%。2004-2010年中国心血管病死因分析显示,高血压性心脏病(hypertensive heart disease, HHD)是继缺血性心脏病、脑血管疾病之后的第三大死因,并呈上升趋势,每年上升幅度为2.08%。高血压致心脏重构是高血压引起心力衰竭的基础,本文就高血压心脏重构的定义、发病机制及病理改变、影像学检查、治疗、预后进行综述。
3D density inversion of gravity gradient data using the extrapolated Tikhonov regularization

We use the extrapolated Tikhonov regularization to deal with the ill-posed problem of 3D density inversion of gravity gradient data. The use of regularization parameters in the proposed method reduces the deviations between calculated and observed data. We also use the depth weighting function based on the eigenvector of gravity gradient tensor to eliminate undesired effects owing to the fast attenuation of the position function. Model data suggest that the extrapolated Tikhonov regularization in conjunction with the depth weighting function can effectively recover the 3D distribution of density anomalies. We conduct density inversion of gravity gradient data from the Australia Kauring test site and compare the inversion results with the published research results. The proposed inversion method can be used to obtain the 3D density distribution of underground anomalies.
A non-local vectorial total variational model for multichannel SAR image speckle suppression

This paper aims at the multichannel synthetic aperture radar (SAR) image speckle reduction. This paper proposes a novel energy minimized regularization model for multichannel image denoising, which is an extension of the non-local total variational model for gray-scale image. It contains two terms, namely the vectorial data fidelity term and the non-local vectorial total variation term. The latter is constructed by high-dimensional non-local gradient that contains the structure information of the multichannel image. The existence and the uniqueness of the solution of the model are proved. A fixed point iterative algorithm is designed to acquire the solution of this model. The convergence property of this algorithm is proved as well. This model is applied to the multipolarimetric and multi-temporal RADARSAT-2 images despeckling. The result shows that this model performs better than the original vectorial total variational model on texture preserving.
Integrated optimization analyses of aerodynamic/stealth characteristics of helicopter rotor based on surrogate model

Based on computational fluid dynamics (CFD) method, electromagnetic high-frequency method and surrogate model optimization techniques, an integration design method about aerodynamic/ stealth has been established for helicopter rotor. The developed integration design method is composed of three modules: integrated grids generation (the moving-embedded grids for CFD solver and the blade grids for radar cross section (RCS) solver are generated by solving Poisson equations and folding approach), aerodynamic/stealth solver (the aerodynamic characteristics are simulated by CFD method based upon Navier-Stokes equations and Spalart-Allmaras (S-A) turbulence model), and the stealth characteristics are calculated by using a panel edge method combining the method of physical optics (PO), equivalent currents (MEC) and quasi-stationary (MQS), and integrated optimization analysis (based upon the surrogate model optimization technique with full factorial design (FFD) and radial basis function (RBF)), an integrated optimization analyses on aerodynamic/stealth characteristics of rotor are conducted. Firstly, the scattering characteristics of the rotor with different blade-tip swept and twist angles have been carried out, then time-frequency domain grayscale with strong scattering regions of rotor have been given. Meanwhile, the effects of swept-tip and twist angles on the aerodynamic characteristic of rotor have been performed. Furthermore, by choosing suitable object function and constraint condition, the compromised design about swept and twist combinations of rotor with high aerodynamic performances and low scattering characteristics has been given at last.
Methods to determine stress profile in ALT based on theoretical life models

With the recent products being more reliable, engineers cannot obtain enough failure or degradation information through the design period and even the product lifetime, therefore, accelerated life test (ALT) has become the most popular way to quantify the life characteristics of products. Test design is the most essential topic, such as testing duration, stress profile, data inference, etc. In this paper, a method and procedure based on theoretical life models is proposed to determine the accelerated stress profile. Firstly, the method for theoretical life calculation is put forward based on the main failure mechanism analysis and the theoretical life models. Secondly, the method is provided to determine the accelerated stress profile, including the method to determine the accelerated stress types and the stress range on the basis of the main failure mechanism analysis, the method to determine the acceleration factor and the accelerated stress level based on life quantitative calculation models, and the collaborative analysis method of the accelerated test time while taking the multiple failure mechanisms into consideration. Lastly, the actuator is taken as an example to describe the procedure of the method and the engineering applicability and the validity are verified.
Mechanism of unconventional aerodynamic characteristics of an elliptic airfoil

The aerodynamic characteristics of elliptic airfoil are quite different from the case of conventional airfoil for Reynolds number varying from about 10~4 to 10~6. In order to reveal the fundamental mechanism, the unsteady flow around a stationary two-dimensional elliptic airfoil with 16% relative thickness has been simulated using unsteady Reynolds-averaged Navier-Stokes equations and the γ- Re_(θt) transition turbulence model at different angles of attack for flow Reynolds number of 5 · 105. The aerodynamic coefficients and the pressure distribution obtained by computation are in good agreement with experimental data, which indicates that the numerical method works well. Through this study, the mechanism of the unconventional aerodynamic characteristics of airfoil is analyzed and discussed based on the computational predictions coupled with the wind tunnel results. It is considered that the boundary layer transition at the leading edge and the unsteady flow separation vortices at the trailing edge are the causes of the case. Furthermore, a valuable insight into the physics of how the flow behavior affects the elliptic airfoil’s aerodynamics is provided.
APEC 会期5个城市空气细颗粒物中重金属健康风险评估

于2014年11月2日-12日,在北京、天津、石家庄、保定和济南等5个城市采集空气细颗粒物样品,微波消解ICP-MS法测定其中10种元素浓度,针对6种有毒有害且关注度高的重金属开展健康风险评估.结果表明,APEC会期5个城市PM_(2.5)日平均值略高于二级标准限值75 μg·m~(-3),在11月4日和11月9日前后出现两次高峰期. 6种有毒有害的重金属浓度依次为Zn > Pb > Cu≈Mn > As > Ni. As致癌风险较低,石家庄>济南>保定>天津>北京,成年人健康风险高于儿童. Ni致癌风险可以忽略.非致癌金属元素风险大小为Mn > Pb > Zn > Cu,Pb、Zn和Cu的风险可以忽略,Mn存在潜在的非致癌风险. APEC期间6种元素的健康风险水平整体低于2012年和2013年同期.
快速溶剂提取-高效液相色谱-二极管紫外阵列/荧光串联法同时测定土壤中18种多环芳烃

建立了快速溶剂(ASE)提取,高效液相色谱-二极管紫外阵列/荧光串联法测定土壤中18种多环芳烃.通过选择净化小柱和仪器条件的优化,实现了18种多环芳烃组分的完全分离及高灵敏度检测,该方法二极管紫外阵列(PDA)检测器和荧光(RF)检测器检出限分别为0. 04-0. 6 μg·kg~(-1)和0. 002-0. 07 μg·kg~(-1) ;4种浓度水平(PDA检测器: 0. 5 μg、2 μg; RF检测器: 0. 02 μg、0. 05 μg)土样加标回收率稳定在82. 8%-122%之间,RSD为1%-5%之间.
中国5个城市儿童家庭室内空气中甲醛、乙醛及总挥发性有机化合物浓度调查分析

为了解儿童住宅室内环境污染现状,于2013-2014年,分别在上海、北京、大连、长沙和武汉,对8-12岁儿童家庭室内空气中甲醛、乙醛和总挥发性有机化合物(TVOC)浓度进行检测.统计分析表明,不同城市住宅室内空气中甲醛、乙醛和TVOC浓度存在显著性差异性(P < 0. 01),冬春季,大连和北京住宅室内空气中甲醛平均浓度高于上海、长沙和武汉.夏秋季住宅客厅和儿童卧室内空气中甲醛和乙醛浓度均高于冬春季(P < 0. 01) . 在夏秋季,上海和大连儿童卧室内空气中甲醛浓度超标率分别为15. 8%和20%,上海住宅客厅和儿童卧室内空气中乙醛浓度超标率分别为5. 3%和10. 5%.
Spatial relation between fluctuating wall pressure and near-wall streamwise vortices in wall bounded turbulent flow

A new view of the spatial relation between fluctuating wall pressure and near-wall streamwise vortices (NWSV) is proposed for wall bounded turbulent flow by use of the direct numerical simulation (DNS) database. The results show that the wall region with low pressure forms just below the strong NWSV, which is mostly associated with the overhead NWSV. The wall region with high pressure forms downstream of the NWSV, which has a good correspondence with the downwash of the fluids induced by the upstream NWSV. The results provide a significant basis for the detection of NWSV.
Scorpion toxin BmK I directly activates Nav1.8 in primary sensory neurons to induce neuronal hyperexcitability in rats

Voltage-gated sodium channels (VGSCs) in primary sensory neurons play a key role in transmitting pain signals to the central nervous system. BmK I, a site-3 sodium channel-specific toxin from scorpion Buthus martensi Karsch, induces pain behaviors in rats. However, the subtypes of VGSCs targeted by BmK I were not entirely clear. We therefore investigated the effects of BmK I on the current amplitude, gating and kinetic properties of Na_v 1.8, which is associated with neuronal hyperexcitability in DRG neurons. It was found that BmK I dose-dependently increased Na_v 1.8 current in smallsized(<25 μm) acutely dissociated DRG neurons, which correlated with its inhibition on both fast and slow inactivation. Moreover, voltage-dependent activation and steady-state inactivation curves of Na_v 1.8 were shifted in a hyperpolarized direction. Thus, BmK I reduced the threshold of neuronal excitability and increased action potential firing in DRG neurons. In conclusion, our data clearly demonstrated that BmK I modulated Na_v 1.8 remarkably, suggesting BmK I as a valuable probe for studying Na_v 1.8. And Na_ 1.8 is an important target related to BmK I-evoked pain.
Effects of different nitrogen fertilizer management practices on wheat yields and N_2O emissions from wheat fields in North China

Nitrogen (N) is one of the macronutrients required for plant growth, and reasonable application of N fertilizers can increase crop yields and improve their quality. However, excessive application of N fertilizers will decrease N use efficiency and also lead to increases in N_2O emissions from agricultural soils and many other environmental issues. Research on the effects of different N fertilizer management practices on wheat yields and N_2O emissions will assist the selection of effective N management measures which enable achieving high wheat yields while reducing N_2O emissions. To investigate the effects of different N management practices on wheat yields and soil N_2O emissions, we conducted field trials with 5 treatments of no N fertilizer (CK), farmers common N rate (AN), optimal N rate (ON), 20% reduction in optimal rate+dicyandiamide (ON80%+DCD), 20% reduction in optimal rate+nano-carbon (ON80%+NC). The static closed chamber gas chromatography method was used to monitor N_2O emissions during the wheat growing season. The results showed that there were obvious seasonal characteristics of N_2O emissions under each treatment and N_2O emissions were mainly concentrated in the sowing- greening stage, accounting for 54.6–68.2% of the overall emissions. Compared with AN, N_2O emissions were decreased by 23.1, 45.4 and 33.7%, respectively, under ON, ON80%+DCD and ON80%+NC, and emission factors were declined by 22.2, 66.7 and 33.3%, respectively. Wheat yield was increased significantly under ON80%+DCD and ON80%+NC by 12.3 and 11.9%, respectively, relative to AN while there was no significant change in yield in the ON treatment. Compared with ON, overall N_2O emissions were decreased by 29.1 and 13.9% while wheat yields improved by 18.3 and 17.9% under ON80%+DCD and ON80%+NC, respectively. We therefore recommend that ON80%+DCD and ON80%+NC be referred as effective N management practices increasing yields while mitigating emissions.
Technical and environmental efficiency of hog production in China - A stochastic frontier production function analysis

This article analyses the technical and environmental efficiency of hog production in China using data from the China Agricultural Product Cost-Benefit Compilation (NDRC 2005–2013) and the First National Census of Pollution: Manual of Discharge Coefficient of Livestock and Poultry Industry (IEDA and NIES 2009). The empirical results show a great variation in environmental efficiency, ranging from 0.344 to 0.973 with a mean value of 0.672 that declines over time. Southwest China is found to be the most environmentally efficient region, while the Northeast and the Northwest are the least efficient. Another finding is that technical and environmental efficiencies are highly correlated in hog production; the most environmentally efficient regions are usually found to have high technical efficiency, and vice versa. In addition, we computed the output elasticities with respect to each factor input. The results show that feed is the most efficient input, with an output elasticity of approximately 0.551, which is much higher than the elasticity of the nitrogen surplus, other capital or labour. The output elasticity with respect to the nitrogen surplus is 0.287 on average. Finally, the scale elasticity in hog production is slightly higher than 1.
Economic evaluation of agricultural pollution control options for China

Environmental sustainability has become a policy priority in China. In agriculture, China has had major success in rehabilitating desertified lands through programs to convert steeply-sloped cropland to forest and limit grazing on sensitive grasslands. However, little has been done in terms of policies for agricultural nutrient management. Runoff and leaching of nutrients in chemical fertilizers and livestock manure are widely acknowledged as significant problems in China. This paper presents an evaluation of agricultural nonpoint pollution control options for China. Options analyzed include design standards (command & control), performance standards, and design and performance incentives. Evaluation criteria include economic efficiency and effectiveness, environmental impact and risk, and social criteria such as equity and food security. The evaluation indicates that the best options for China involve subsidies to farmers for changing production practices in order to reduce nonpoint emissions, combined with appropriate farmer education and technical assistance.
Tolerance of disturbance by humans in long-time resident and recent colonist urban doves

Background: A critical trait for successful urban dwelling by birds is the ability to tolerate high levels of disturbing stimulation by humans. If such tolerance is partly acquired gradually after colonization, species with a long history of residence in cities are likely to be more tolerant of such stimulation than recent urban colonists, but this has not often been tested. Methods: We tested whether introduced Rock (Columba livia) and Spotted (Streptopelis chinensis) Doves, historically long-term residents of Melbourne, Australia, were more tolerant of disturbance by humans than the very recent colonist, the native Crested Pigeon (Ochyphaps lophotes) by comparing the Flight Initiation Distances (FID) and time allocations to vigilance during foraging of all three species in urban Melbourne. That all three species are members of the Columbiformes reduces the possibility that any species differences in tolerance are simply phylogenetic in origin. Results: Flight initiation distance was shorter in Rock Doves than in the other two species, which did not differ in approachability by a human. Rock Doves retreated from an approaching human mainly by walking a relatively short distance, Crested Pigeons mainly by running a relatively short distance and Spotted Doves primarily by flying a comparatively long distance. The time allocation to anti-predator vigilance of Rock Doves was smaller than that of the other two species, whose allocations were similar. Conclusions: The very recent colonist of eastern Melbourne, the Crested Pigeon, was not the least tolerant of disturbance by humans of the three related species. Natural selection for tolerance therefore probably cannot entirely explain the pattern of tolerance evident among these urban dove species and behavioural flexibility is probably involved. Length of residency in a city is not an infallible guide to a species’ level of tolerance of disturbance by humans.
Ultra-sensitive graphene strain sensor for sound signal acquisition and recognition

A wearable and high-precision sensor for sound signal acquisition and recognition was fabricated from thin films of specially designed graphene woven fabrics (GWFs). Upon being stretched, a high density of random cracks appears in the network, which decreases the current pathways, thereby increasing the resistance. Therefore, the film could act as a strain sensor on the human throat in order to measure one’s speech through muscle movement, regardless of whether or not a sound is produced. The ultra-high sensitivity allows for the realization of rapid and low-frequency speech sampling by extracting the signature characteristics of sound waves. In this study, representative signals of 26 English letters, typical Chinese characters and tones, and even phrases and sentences were tested, revealing obvious and characteristic changes in resistance. Furthermore, resistance changes of the graphene sensor responded perfectly with pre-recorded sounds. By combining artificial intelligence with digital signal processing, we expect that, in the future, this graphene sensor will be able to successfully negotiate complex acoustic systems and large quantities of audio data.