mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Authigenic Gypsum in Gas-Hydrate Associated Sediments from the East Coast of India (Bay of Bengal)

Authigenic gypsum crystals, along with pyrite and carbonate mineralization, predominantly calcites were noticed in distinct intervals in a 32 m long piston core, collected in the gas hydrate-bearing sediments in the northern portion of the Krishna-Godavari basin, eastern continental margin of India at a water depth of 1691 m. X-ray diffraction and energy dispersive spectrum studies confirm presence of pyrite, gypsum, calcite, and other mineral aggregates. The occurrence of gypsum in such deep sea environment is intriguing, because gypsum is a classical evaporite mineral and is under saturated with respect to sea water. Sedimentological, geochemical evidences point to diagenetic formation of the gypsum due to oxidation of sulphide minerals (i.e. pyrite). Euhedral, transparent gypsum crystals, with pyrite inclusions are cemented with authigenic carbonates, possibly indicating that they were formed authigenically in situ in the gas hydrate-influenced environment due to late burial diagenesis involving sulphate reduction and anaerobic oxidation of methane (AOM). Therefore, the authigenic gypsums found in sediments of the Krishna-Godavari and Mahanadi offshore regions could be seen as one of the parameters to imply the presence of high methane flux possibly from gas hydrate at depth.
A robust solution for hesitate phenomenon in pick up process of aerospace electromagnetic relay

As for aerospace electromagnetic relay (AEMR) which is of small batches and having difficulty in automatic production, the uncertainty phenomenon is remarkable due to excessive manual work involved in the assembly and adjustment processes. This kind of uncertainty may increase the coil voltage difference (CVD) caused by hesitate phenomenon in the pick up process of AEMR. Taking a certain type of AEMR for example, the CVD problem in the actual producing process has been studied in this paper. The primary cause of this issue, two-steps of armature motion (namely hesitate phenomenon) in the pick up process, has been found by analyzing the matching characteristics of electromagnetic and mechanical torques of AEMR. Through the optimization of the matching characteristics, the two-steps of armature motion problem is solved by robust design of the return reed which is a key part of AEMR. The validity of this research has been proved by the comparison of characteristics of AMER before and after the optimization.
Impact of the North Atlantic sea surface temperature tripole on the East Asian summer monsoon

A strong (weak) East Asian summer monsoon (EASM) is usually concurrent with the tripole pattern of North Atlantic SST anomalies on the interannual timescale during summer, which has positive (negative) SST anomalies in the northwestern North Atlantic and negative (positive) SST anomalies in the subpolar and tropical ocean. The mechanisms responsible for this linkage are diagnosed in the present study. It is shown that a barotropic wave-train pattern occurring over the Atlantic-Eurasia region likely acts as a link between the EASM and the SST tripole during summer. This wave-train pattern is concurrent with geopotential height anomalies over the Ural Mountains, which has a substantial effect on the EASM. Diagnosis based on observations and linear dynamical model results reveals that the mechanism for maintaining the wave-train pattern involves both the anomalous diabatic heating and synoptic eddy-vorticity forcing. Since the North Atlantic SST tripole is closely coupled with the North Atlantic Oscillation (NAO), the relationships between these two factors and the EASM are also examined. It is found that the connection of the EASM with the summer SST tripole is sensitive to the meridional location of the tripole, which is characterized by large seasonal variations due to the north-south movement of the activity centers of the NAO. The SST tripole that has a strong relationship with the EASM appears to be closely coupled with the NAO in the previous spring rather than in the simultaneous summer.
多孔金属夹层圆柱壳的热机响应分析、优化设计及应用研究

脉冲爆震发动机(Pause Detonation Engine,PDE)是21世纪最有前途的革命性航空航天动力之一,是一种利用脉冲式爆震波产生推力的新概念发动机.PDE的工作环境很特殊:高温(2000-3000K)、高压(20-30atm)、间歇性高速移动(1500-3000m/s)的热机冲击,为保证爆震燃烧室(爆震管)在如此恶劣的环境下稳定、可靠的运行,其强度设计、减振降噪和寿命技术等都是关键课题.多孔金属材料具有很多优良的性能,如超轻、高比强度比刚度、高韧性耐冲击、高效散热隔热以及噪声控制等,尤其是通过合理设计材料微结构可以实现多功能集成.将多孔金属材料应用于脉冲爆震发动机的结构设计无疑是一种很好的尝试和创新.将多孔金属应用于PDE燃烧室,有望设计一种集承载和主动散热多功能于一体的爆震燃烧室(图1).本文主要围绕高温环境下二维棱镜多孔金属夹层圆柱壳在高速移动冲击内压作用下的结构响应和优化设计展开了一系列研究.研究成果可为多孔金属夹层燃烧室的结构分析和轻量化设计提供理论方法(图2),对多功能PDE燃烧室从概念设计到制造、工装具有一定工程参考价值.主要工作包括以下几个方面.
面向对象的极化干涉SAR影像分割算法研究

根据高分辨率SAR影像的特点,基于目标分解理论定义极化SAR异质度,利用极化干涉相干最优目标分解思想提出极化干涉SAR异质度,并利用ESAR提供的数据对分割算法进行试验研究。将极化干涉数据的分割结果和极化数据的分割结果进行对比,从而验证了极化干涉SAR异质度的分割精度更高。
基于球谐函数模型的GPS差分码延迟估计

电离层延迟是GNSS观测值中最大的误差源,因此如何利用GNSS观测值确定高精度电离层模型逐渐成为实时导航、定位及大气相关研究的重要内容。在通常采用组合观测值建立模型的方法中,精确估计电离层总电子含量(TEC)的重要误差之一是差分码硬件延迟(DCBs)。为了实时得到P1、P2、C2相互间硬件差分码延迟偏差,本文采用IGS跟踪站的观测数据并利用载波平滑后的差分伪距建立观测方程,对卫星和接收机硬件差分码延迟偏差进行实时解算。经比较模型解算DCB值与IGS最大差异不超过0.8 ns,C1、P1码延迟偏差72%差异值小于0.3 ns,P1、P2的74%差异值小于0.3 ns。
Improved photovoltaic properties of Si quantum dots/SiC multilayers-based heterojunction solar cells by reducing tunneling barrier thickness

Si quantum dots (Si QDs)/SiC multilayers were fabricated by annealing hydrogenated amorphous Si/ SiC stacked structures prepared in plasma enhanced chemical vapor deposition (PECVD) system. The micro- structures were examined by transmission electron micro- scopy (TEM) and Raman spectroscopy, and results demonstrate the formation of Si QDs. Moreover, p-i-n devices containing Si QDs/SiC multilayers were fabricated, and their photovoltaic property was investigated. It was found that these devices show the good spectral response in a wide wavelength range (400-1200 nm). And it was also observed that by reducing the thickness of SiC layer from 4 to 2 nm, the external quantum efficiency was obviously enhanced and the short circuit current density(Jsc) was increased from 17.5 to 28.3 mA/cm2, indicating the collection efficiency of photo-generated carriers was improved due to the reduced SiC barriers.
Review on SOA-MZI-based photonic add/drop and switching operations

Semiconductor optical amplifier-Mach-Zehnder interferometer (SOA-MZI) is a technologically mature optical device that can be exploited for a wide range of operations on both amplitude and phase modulated signals, with performance limited by the carrier lifetime in the SOAs. Recent advances on SOA structures have demonstrated their suitability for high quality, ultra-fast photonic signal processing, making SOA-MZI a good candidate for elaborating signals in new generation high-capacity optical networks. Dynamic wavelength switching/routing and add/drop operations are expected to bring benefits in future optical networks in terms of improved system flexibility and efficiency. The capability of performing such operations directly in the optical domain can significantly reduce the number of opto/electrical and electro/optical conversions in the routing nodes, reducing their power consumption and their latency time. Moreover, since phase-shift keying (PSK) formats or other advanced modulation formats involving both amplitude and phase modulation, start to coexist in optical communication systems with the conventional on-off keying (OOK) modulation format, the availability of a single device, suitable for processing all these different signals, is mandatory. The SOA-MZI fits all these requirements for both OOK and constant-envelope phase-modulated signals, providing a compact and flexible solution. Here we review on the use of the SOA-MZI for carrying out all-optical switching operations, by realizing wavelength conversion and add/drop functionalities, both for OOK and differential binary phase shift keying (DPSK) signals up to 40 Gb/s. Power penalties lower than 2 dB are demonstrated in all cases.
Advanced materials: adsorbent and catalyst forenvironmental application

With the economic growth, the environmental pollution is still a challenge for sustainable development all over the world. In order to prevent, reduce and remediate the various environmental problems, it is crucial to develop innovative and efficient materials to remove and decompose pollutants from air or water in that the efficient adsorbents and catalysts are playing an important role in the process of physical and chemical reactions. Therefore, the editors of FESE proposed to publish one special issue, and report the original research and review papers about advanced adsorbents and catalysts that are potentially or widely applied in environmental protection.
Catalytic ozonation performance and surface property of supported Fe_3O_4 catalysts dispersions

Fe_3O_4 was supported on mesoporous Al_2O_3 or SiO_2 (50 wt.%) using an incipient wetness impregnation method, and Fe_3O_4/Al_2O_3 exhibited higher catalytic efficiency for the degradation of 2,4-dichlorophenoxyacetic acid and para-chlorobenzoic acid aqueous solution with ozone. The effect and morphology of supported Fe_3O_4 on catalytic ozonation performance were investigated based on the characterization results of X-ray diffraction, X-ray photoelectron spectroscopy, BET analysis and Fourier transform infrared spectroscopy. The results indicated that the physical and chemical properties of the catalyst supports especially their Lewis acid sites had a significant influence on the catalytic activity. In comparison with SiO_2, more Lewis acid sites existed on the surface of Al_2O_3, resulting in higher catalytic ozonation activity. During the reaction process, no significant Fe ions release was observed. Moreover, Fe_3O_4/Al_2O_3 exhibited stable structure and activity after successive cyclic experiments. The results indicated that the catalyst is a promising ozonation catalyst with magnetic separation in drinking water treatment.
Comparison of optimal capacitor placement methods in radial distribution system with load growth and ZIP load model

In this paper, a combined power loss sensitivity (PLS) index-based approach is proposed to determine the optimal location of the capacitors in the radial distribution system (RDS) based on the real and reactive combined loss sensitivity index, as capacitor placement not only reduces real power loss with voltage profile improvement but also reduces reactive power loss due to the reactive power compensation in the network. The results have been obtained with the existing methods of power loss index (PLI) and index vector (IV) method for comparison. Besides, the optimal placement has been obtained with the proposed method as well as existing methods and the total kVar support has been obtained. In addition, the results of net cost savings for the 10-, 34-, and 69-bus systems are obtained for comparison. Moreover, the results have been obtained for a large system of 85 buses to validate the results with combined sensitivity based approach. Furthermore, the load growth factor has been considered in the study which is essential for the planning and expansion of the existing systems, whereas the impact of the realistic load model as ZIP load model has been considered for the study of all the systems.
Prediction of cutting forces in machining of unidirectional glass fiber reinforced plastics composite

Machining of plastic materials has become increasingly important in any engineering industry subsequently the prediction of cutting forces. Forces quality has greater influence on components, which are coming in contact with each other. So it becomes necessary to measure and study machined forces and its behavior. In this research work, experimental investigations are conducted to determine the effects of cutting conditions and tool geometry on the cutting forces in the turning of the unidirectional glass fiber reinforced plastics (UD-GFRP) composites. In this experimental study, carbide tool (K10) having different tool nose radius and tool rake angle is used. Experiments are conducted based on the established Taguchi's technique L_(18) orthogonal array on a lathe machine. It is found that the depth of cut is the cutting parameter, which has greater influence on cutting forces. The effect of the tool nose radius and tool rake angles on the cutting forces are also considerably significant. Based on statistical analysis, multiple regression model for cutting forces is derived with satisfactory coefficient (R~2). This model proved to be highly preferment for predicting cutting forces.
An assemble-to-order production planning with the integration of order scheduling and mixed-model sequencing

For assemble-to-order enterprises, both order scheduling and mixed-model sequencing need to be taken into consideration in the formulation of order-oriented assembly plan. First, determining production priority for the received orders, and then conducting assembly sequence to the mixed-model products in each order. Order scheduling is aimed to ensure order delivery with the optimization goal of minimal total overdue time, while product sequencing is aimed to minimize the makespan so as to meet the requirement on completion time of the order. In the end, the paper establishes a mixed integer programming model based on an industrial case, and makes programming calculation with Xpress-MP to accomplish an order-oriented assembly plan conforming to actual production.
Analysis of planetary gear transmission in non-stationary operations

Planetary gearboxes operate usually in nonstationary conditions generated mainly by variable loads applied to these transmissions. In order to understand the dynamic behavior of planetary gearboxes in such conditions, a mathematic model is developed including driving unit, transmission and load. The variability of load induces a variable speed of the transmission which is taken into account when characterizing the main dynamic parameter of the transmission which is the mesh stiffness function. This function is not periodic following the variability of the transmission speed. The computation of the dynamic response shows an intimate relation between the vibration amplitude level and the load value. As the load increase the vibration level increase. A combined amplitude and frequency modulation is observed which is well characterized using Short Time Fourier transform more suited than the spectral analysis.
Cost of non-renewable energy in production of wood pellets in China

Assessing the extent to which all bio-fuels that are claimed to be renewable are in fact renewable is essential because producing such renewable fuels itself requires some amount of non-renewable energy (NE) and materials. Using hybrid life cycle analysis (LCA)—from raw material collection to delivery of pellets to end users—the energy cost of wood pellet production in China was estimated at 1.35 J/J, of which only 0.09 J was derived from NE, indicating that only 0.09 J of NE is required to deliver 1 J of renewable energy into society and showing that the process is truly renewable. Most of the NE was consumed during the conversion process (46.21%) and delivery of pellets to end users (40.69%), during which electricity and diesel are the two major forms of NE used, respectively. Sensitivity analysis showed that the distance over which the pellets are transported affects the cost of NE significantly. Therefore the location of the terminal market and the site where wood resources are available are crucial to saving diesel.
Accurate prediction of protein dihedral angles through conditional random field

Identifying local conformational changes induced by subtle differences on amino acid sequences is critical in exploring the functional variations of the proteins. In this study, we designed a computational scheme to predict the dihedral angle variations for different amino acid sequences by using conditional random field. This computational tool achieved an accuracy of 87% and 84% in 10-fold cross validation in a large data set for φ and Ψ, respectively. The prediction accuracies of φ and Ψ are positively correlated to each other for most of the 20 types of amino acids. Helical amino acids can achieve higher prediction accuracy in general, while amino acids in beet sheet have higher accuracy at specific angular regions. The prediction accuracy of φ is negatively correlated with amino acid flexibility represented by Vihinen Index. The prediction accuracy of φ can also be negatively correlated with angle distribution dispersion.
Physiological effects of climate warming on flowering plants and insect pollinators and potential consequences for their interactions

Growing concern about the influence of climate change on flowering plants, pollinators, and the mutualistic interactions between them has led to a recent surge in research. Much of this research has addressed the consequences of warming for phenological and distributional shifts. In contrast, relatively little is known about the physiological responses of plants and insect pollinators to climate warming and, in particular, how these responses might affect plant-pollinator interactions. Here, we summarize the direct physiological effects of temperature on flowering plants and pollinating insects to highlight ways in which plant and pollinator responses could affect floral resources for pollinators, and pollination success for plants, respectively. We also consider the overall effects of these responses on plant-pollinator interaction networks. Plant responses to warming, which include altered flower, nectar, and pollen production, could modify floral resource availability and reproductive output of pollinating insects. Similarly, pollinator responses, such as altered foraging activity, body size, and life span, could affect patterns of pollen flow and pollination success of flowering plants. As a result, network structure could be altered as interactions are gained and lost, weakened and strengthened, even without the gain or loss of species or temporal overlap. Future research that addresses not only how plant and pollinator physiology are affected by warming but also how responses scale up to affect interactions and networks should allow us to better understand and predict the effects of climate change on this important ecosystem service.
A wide range sigma-delta fractional-N frequency synthesizer with adaptive frequency calibration

A wide range fractional-N frequency synthesizer in 0.18μm RF CMOS technology is implemented. A switched-capacitors bank LC-tank VCO and an adaptive frequency calibration technique are used to expand the frequency range.A 16-bit third-order sigma-delta modulator with dither is used to randomize the fractional spur. The active area is 0.6 mm~2.The experimental results show the proposed frequency synthesizer consumes 4.3 raA from a single 1.8 V supply voltage except for buffers.The frequency range is 1.44-2.11 GHz and the frequency resolution is less than 0.4 kHz.The phase noise is -94 dBc/Hz @ 100 kHz and -121 dBc/Hz @ 1 MHz at the output of the prescaler with a loop bandwidth of approximately 120 kHz.The performance meets the requirements for the multi-band and multi-mode transceiver applications.
A wide load range,multi-mode synchronous buck DC-DC converter with a dynamic mode controller and adaptive slope compensation

A synchronous buck DC-DC converter with an adaptive multi-mode controller is proposed.In order to achieve high efficiency over its entire load range,pulse-width modulation(PWM),pulse-skip modulation(PSM) and pulse-frequency modulation(PFM) modes were integrated in the proposed DC-DC converter.With a highly accurate current sensor and a dynamic mode controller on chip,the converter can dynamically change among PWM, PSM and PFM control according to the load requirements.In addition,to avoid power device damage caused by inrush current at the start up state,a soft-start circuit is presented to suppress the inrush current.Furthermore,an adaptive slope compensation(SC) technique is proposed to stabilize the current programmed PWM controller for duty cycle passes over 50%,and improve the degraded load capability due to traditional slope compensation.The buck converter chip was simulated and manufactured under a 0.35μm standard CMOS process.Experimental results show that the chip can achieve 79%to 91%efficiency over the load range of 0.1 to 1000 mA.
Development of aluminum-doped ZnO films for a-Si:H/μc-Si:H solar cell applications

This study deals with the optimization of direct current(DC) sputtered aluminum-doped zinc oxide (AZO) thin films and their incorporation into a-Si:H/μc-Si:H tandem junction thin film solar cells aiming for high conversion efficiency.Electrical and optical properties of AZO films,i.e.mobility,carrier density,resistivity, and transmittance,were comprehensively characterized and analyzed by varying sputtering deposition conditions, including chamber pressure,substrate temperature,and sputtering power.The correlations between sputtering processes and AZO thin film properties were first investigated.Then,the AZO films were textured by diluted hydrochloric acid wet etching.Through optimization of deposition and texturing processes,AZO films yield excellent electrical and optical properties with a high transmittance above 81%over the 380-1100 nm wavelength range,lowsheet resistance of 11Ω/□and high haze ratio of 41.3%.In preliminary experiments,the AZO films were applied to a-Si:H/μc-Si:H tandem thin film solar cells as front contact electrodes,resulting in an initial conversion efficiency of 12.5%with good current matching between subcells.
The impact of germanium in strained Si/relaxed Si_(1-x)Ge_x on carrier performance in non-degenerate and degenerate regimes

The impact of the fraction of germanium on the carrier performance of two-dimensional strained silicon, which embraces both the non-degenerate and degenerate regimes,is developed.In this model,the Fermi integral of order zero is employed.The impact of the fraction of germanium on the relaxed Si_(1-x)Ge_x substrate(x),carrier concentration and temperature is reported.It is revealed that the effect of x on the hole concentration is dominant for a normalized Fermi energy of more than three,or in other words the non-degenerate regime.On the contrary, the x gradient has less influence in the degenerate regime.Furthermore,by increasing x there is an increase in the intrinsic velocity,particularly with high carrier concentration and temperature.
Optical simulation of phosphor layer of white LEDs

A Matlab(2009a) program was developed to simulate the photons emitted by the LED chips.The photons’transmission,reflection,and refraction in phosphor layers with different shapes were calculated in this program.The CCT was calculated at different emergent angles with different layer profiles,such as planar layer, hemispherical layer(with different diameters),half ellipsoid layer and other irregular shapes.As a consequence of optimization of angular color uniformity,the trend of configuration of the phosphor layer was discussed and analyzed.
A dual-path,current-sensing resistor-free boost LED driver with fast PWM dimming

A boost LED driver featuring a high PWM dimming ratio and optimized efficiency is presented.This LED driver,which has a low dropout voltage and is able to drive 3-7 LEDs in series with constant output current and fast PWM dimming,provides an alternative technique for brightness adjustment.A dual-path control scheme with automatic switching and state maintenance is proposed.Meanwhile,a cascode current mirror structure is applied with the output transistor multiplexed as an LED PWM dimming transistor.Implemented in 0.5μm 25 V BCD process,the measurement results show that a voltage conversion range of 5 V input to 6-24 V output with constant output current is obtained.With automatically switching dual-path control and an optimized current mirror,the response time during PWM dimming is reduced to as low as 240 ns and the efficiency keeps above 89%over a wide PWM dimming ratio @ 250 mA output current.