bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of compact inductive energy storage pulsed-power generator driven by 13 kV SiC-MOSFET
Authors: Takahashi Katsuyuki , Saito Ryo , Onodera Taichiro , Takaki Koichi , Kitai Hidenori , Sakamoto Kunihiro 
Published: June 2021

A compact inductive energy storage (IES) pulsed-power generator that is driven by a novel 13 kV silicon carbide (SiC)-MOSFET is developed and molded into a compact modified TO-268. In this article, the switching characteristics required for IES pulsed-power generator development are evaluated. The maximum slew rates at MOSFET turn-on and turn-off are 157 and 129 kV/μs, respectively, at an input voltage of 10 kV. The maximum current flow from the drain to the source terminal is limited to 128 A during short-circuit switching. The on-resistance between the drain and source terminals increases during the SiC-MOSFET’s on state. It increases with the voltage and its minimum value is 1.07 Ω. These characteristics show that the device is suitable for use as an opening switch because of its low on-resistance and rapid large-current cutoff at high operating voltages. The characteristics of an IES pulsed-power generator composed of a SiC-MOSFET, a capacitor, and a pulsed transformer with a turn ratio of 5:15 are also evaluated. The output voltage peak and full width at half maximum reach 31.4 kV and 55 ns, respectively, at a charging voltage of 1100 V. The maximum energy transfer efficiency is 50.2% of the input energy with a load resistance of 2.5 kΩ. The results show that the MOSFET has excellent potential to support the development of a compact plasma generation system that offers better performance pulsed-power generators driven by semiconductor devices.
Fifty million years of beetle evolution along the Antarctic Polar Front
Authors: Baird Helena P. , Shin Seunggwan , Oberprieler Rolf G. , Hullé Maurice , Vernon Philippe , Moon Katherine L. , Adams Richard H. , McKenna Duane D. , Chown Steven L. 
Published: June 2021

SignificanceThe Antarctic environment is famously inhospitable to most terrestrial biodiversity, traditionally viewed as a driver of species extinction. Combining population- and species-level molecular data, we show that beetles on islands along the Antarctic Polar Front diversified in response to major climatic events over the last 50 Ma in surprising synchrony with the region’s marine organisms. Unique algae- and moss-feeding habits enabled beetles to capitalize on cooling conditions, which resulted in a decline in flowering plants—the typical hosts for beetles elsewhere. Antarctica’s cooling paleoclimate thus fostered the diversification of both terrestrial and marine life. Climatically driven evolutionary processes since the Miocene may underpin much of the region’s diversity, are still ongoing, and should be further investigated among Antarctic biota.
Photosynthesis and productivity.
Authors: Singh Vinod K. , Soni Manoj K. 
Published: June 2021

Abstract

Knowledge on the responses of guava to environmental factors such as light, temperature, water availability and CO2 concentration is essential to determine the effect of suboptimal environmental conditions and to manage the crop for maximum productivity. This chapter aims to highlight the current understanding and the possible effects of environmental factors on the whole physiology of guava trees as expressed by growth, yield, fruit quality and photosynthetic features. Possible areas of future research are also suggested.
The global cut flower and foliage marketplace.
Authors: Faust James E. , Dole John M. 
Published: June 2021

Abstract

This chapter describes the evolving geography of cut flower and foliage markets, and identifies the factors driving the location of cut flower production. It also identifies the major cut flower species grown and sold internationally followed by descriptions of the production and markets by continent and country. The chapter also diagrams the increasingly diverse and complex ways that flowers are marketed and travel from the growers to the final customers, and then describes the trends that are driving the industry in new directions.
Estimation of microtexture region orientation distribution functions using eddy current data
Authors: Homa Laura , Cherry Matthew , Wertz John 
Published: June 2021

Abstract
Microtexture regions (MTRs) within titanium alloys are collections of grains with similar crystallographic orientation. The presence of MTRs can be detrimental to the life of an engine component; as such, a method to detect and characterize MTRs is needed. One potential technique to characterize MTRs is eddy current (EC) testing, which is a nondestructive evaluation technique that is sensitive to the changes in local conductivity due to changes in local crystallographic orientation. While it has been established in the literature that EC methods are sensitive to the presence of MTRs, work has begun only recently to determine the ability of EC to characterize MTRs. In this work, we develop an algorithm to estimate the orientation distribution function of an MTR of interest using EC data. The method relies on an application of the central limit theorem, and the inverse problem is solved in using a likelihood-free technique. Numerical examples using simulated EC data are shown.
Dissipative preparation of W states in trapped ion systems
Authors: Cole Daniel C , Wu Jenny J , Erickson Stephen D , Hou Pan-Yu , Wilson Andrew C , Leibfried Dietrich , Reiter Florentin 
Published: June 2021

Abstract
We present protocols for dissipative entanglement of three trapped-ion qubits and discuss a scheme that uses sympathetic cooling as the dissipation mechanism. This scheme relies on tailored destructive interference to generate any one of six entangled W states in a three-ion qubit space. Using a beryllium–magnesium ion crystal as an example system, we theoretically investigate the protocol’s performance and the effects of likely error sources, including thermal secular motion of the ion crystal, calibration imperfections, and spontaneous photon scattering. We estimate that a fidelity of ∼98% may be achieved in typical trapped ion experiments with ∼1 ms interaction time. These protocols avoid timescale hierarchies for faster preparation of entangled states.
Energy system developments and investments in the decisive decade for the Paris Agreement goals
Authors: Bertram Christoph , Riahi Keywan , Hilaire Jérôme , Bosetti Valentina , Drouet Laurent , Fricko Oliver , Malik Aman , Nogueira Larissa Pupo , van der Zwaan Bob , van Ruijven Bas , van Vuuren Detlef , Weitzel Matthias , Longa Francesco Dalla , de Boer Harmen-Sytze , Emmerling Johannes , Fosse Florian , Fragkiadakis Kostas , Harmsen Mathijs , Keramidas Kimon , Kishimoto Paul Natsuo , Kriegler Elmar , Krey Volker , Paroussos Leonidas , Saygin Deger , Vrontisi Zoi , Luderer Gunnar 
Published: June 2021

Abstract
The Paris Agreement does not only stipulate to limit the global average temperature increase to well below 2 °C, it also calls for ‘making finance flows consistent with a pathway towards low greenhouse gas emissions’. Consequently, there is an urgent need to understand the implications of climate targets for energy systems and quantify the associated investment requirements in the coming decade. A meaningful analysis must however consider the near-term mitigation requirements to avoid the overshoot of a temperature goal. It must also include the recently observed fast technological progress in key mitigation options. Here, we use a new and unique scenario ensemble that limit peak warming by construction and that stems from seven up-to-date integrated assessment models. This allows us to study the near-term implications of different limits to peak temperature increase under a consistent and up-to-date set of assumptions. We find that ambitious immediate action allows for limiting median warming outcomes to well below 2 °C in all models. By contrast, current nationally determined contributions for 2030 would add around 0.2 °C of peak warming, leading to an unavoidable transgression of 1.5 °C in all models, and 2 °C in some. In contrast to the incremental changes as foreseen by current plans, ambitious peak warming targets require decisive emission cuts until 2030, with the most substantial contribution to decarbonization coming from the power sector. Therefore, investments into low-carbon power generation need to increase beyond current levels to meet the Paris goals, especially for solar and wind technologies and related system enhancements for electricity transmission, distribution and storage. Estimates on absolute investment levels, up-scaling of other low-carbon power generation technologies and investment shares in less ambitious scenarios vary considerably across models. In scenarios limiting peak warming to below 2 °C, while coal is phased out quickly, oil and gas are still being used significantly until 2030, albeit at lower than current levels. This requires continued investments into existing oil and gas infrastructure, but investments into new fields in such scenarios might not be needed. The results show that credible and effective policy action is essential for ensuring efficient allocation of investments aligned with medium-term climate targets.
Analysis on Deformation and Stability of Tunnel Anchor Excavation under Broken Rock Mass
Authors: Qing Yuan , Ziping Zhang , Qihuan Xiong , Shihao Chen 
Published: June 2021

Abstract
Based on the concrete engineering support of the tunnel anchor of the Dadu River Bridge on the Sichuan-Tibet Railway, the geological background of broken rock mass, extremely developed joints and fissures, and poor self-stability of surrounding rock within the range of side anchors in Chengdu, a three-dimensional elastoplastic numerical calculation method is used. The current engineering geological conditions and the tunnel anchor design plan are to establish a three-dimensional fine numerical simulation model of the Chengdu side tunnel anchor that comprehensively considers rock mass unloading, stratum classification, and anchor tunnel excavation and support structure. The “excavation-support” process in each construction footage is simulated to realize the three-dimensional calculation of the dynamic construction and support of anchor tunnels, and to study the surrounding rock deformation, stress and plastic zone distribution changes during the excavation process. Comprehensive analysis found that the deformation of surrounding rock during excavation shows that it develops toward the empty surface, and the displacement distribution is obviously affected by the distribution of ground stress and rock formation. The greater the buried depth, the greater the deformation of the surrounding rock.
Analysis of the Existing Seismic-Resistant Concrete Structure
Authors: Ling Xiaoming 
Published: June 2021

Abstract
The seismic-resistant concrete structure is an important component in the buildings and plays a key role in many countries, like Japan, Philippine and America. Different from traditional ways, the use of precast concrete in those areas is feasible now. Regardless of the progress in the area of precast concrete, the major problem of joint technology persists. This paper aims to review the existing precast concrete structures and some other seismic-resistant concrete structures. It is concluded from this review that the performance of precast concrete is the same as traditional methods and has its benefits in construction and economic aspects.
Vibration Response of Brick Concrete Buliding under Shaft Blasting
Authors: Gao Shang , Ji Xinyu , Ding Xinyu , Wang Hailiang , Jiang Shibin , Zhao Chen 
Published: June 2021

Abstract
During the blasting construction, the problem of building vibration caused by blasting cannot be ignored. Therefore, this paper uses the measured blasting seismic wave of a shaft in Qingdao Metro as the input parameter to conduct numerical simulation to research the influence of blasting vibration of shaft on brick concrete bulidings. The results show that The Z-direction vibration velocity has obvious local amplification on the roof, and the amplification factor is 1.4-1.9 relative to the top floor. The magnification factor on the backward side is smaller than the magnification factor on the frontward side, and the elevation magnification effect gradually weakens as the elevation difference increases. HHT (Hilbert-Huang Transform) method is used to analyze blasting seismic wave signals, when the blasting seismic wave propagates from the first floor of the brick concrete buliding to the roof, the energy is reduced by about 67%-80%. The frequency band of 0-30 Hz is the main range of blasting energy distribution in brick concrete buildings, and attention should be paid to resonance phenomenon.
Study on settlement characteristics of deep soft strata by vacuum preloading
Authors: Li Hao , Li Xuesong , Qin Xing 
Published: June 2021

Abstract
In order to study the vacuum preloading settlement characteristics of Hengli Island soft strata, the monitoring data of the vacuum preloading area are analyzed, and the hyperbolic method and the three-points method are used to predict the final settlement. The results show that the variation trend of settlement, vacuum degree and water level has a high consistency. The larger the calculated data span, the larger the calculated result. The three-points method is closer to the measured value than the hyperbolic method, the ratio of the three-points method to the measured value was 94%∼110%, and the latter 110%∼120%. However, the three-points method is sensitive to settlement saltation, and the calculation result error will be large if the calculated data span the saltation region, while the hyperbolic method is not sensitive to settlement saltation. According to the settlement rate and predicted settlement, the unloading time is earlier than the actual unloading time, which provides a reference for the reasonable evaluation of the unloading time and the reduction of the low-efficiency preloading time.
Methods to Improve the Performance of Aluminum Alloy
Authors: Shu Muwei 
Published: June 2021

Abstract
Aluminum alloy has a lot of benefits including high strength, great ductility and low density. It is widely used in vehicle engineering, aviation, aerospace and so on. However, there is a higher requirement for aluminum alloy in these fields. For instance, higher strength, higher hardness, higher elongation and other performances are needed. Changing the content of certain elements, combination with graphene, plasma spraying and heat treatment might be four effective methods to improve the performance of the aluminum alloy. The experiments verify the effectiveness of each method. Still, there should be more studies on these methods to reveal the principle of each method.
Analysis on deformation characteristics of Hengli Island soft strata by vacuum preloading
Authors: Li Xuesong , Li Yongzhi 
Published: June 2021

Abstract
The deformation monitoring value of Hengli Island soft strata by vacuum preloading was analyzed. The results show that the vertical settlement and lateral displacement of strata mainly occur in the first 20 days. The negative pressure attenuation at different positions is quite different, and the average negative pressure attenuation rate with depth is about 3.2kPa/m. The difference of additional stress by the overlying water leads to the average settlement of the central area of the preloading area is greater than that of the marginal area. The settlement calculation results of Layered Summation Method are basically consistent with the measured values. According to the lateral displacement law of different projects, it is concluded that the lateral displacement has a progressive relationship with the vacuum preloading area half width, the prefabricated vertical drains (PVDs) length and the vertical settlement ratio of about 10 times, and the calculated value of lateral displacement agrees well with the measured value.
Research on influencing factors of rubber concrete performance based on grey correlation theory
Authors: Zhao Z F , Chen C L , Li H Y , Li L F , Ren C B 
Published: June 2021

Abstract
Based on the experiment and grey system theory, the influence on slump and compressive strength of rubber concrete are analyzed systematically under the rubber grain gradation mass, the content of rubber grain substitution and whether the rubber surface is pretreated. The influence rule of each factor on the slump and compressive strength is consistent. The influence order is as follows: The mass percentage of rubber particle grading is more than the amount of rubber particle replacing, which is more than whether the rubber surface is pretreated. The mass percentage of rubber particle grading and the amount of rubber particle replacing is more than 0.6 and whether the rubber surface is pretreated that is less than 0.6. In view of this situation, considering whether the assignment condition of rubber surface pretreated is reasonable, this problem needs further study. The results of this paper provide a theoretical reference for the main factors concerned in the mix design of rubber concrete.
Spatialization of population based on Xgboost with multi-source data
Authors: Li Yinxing , Liu Minghao 
Published: June 2021

Abstract
Aiming at the problem that demographic data cannot visually and clearly show the true distribution of population and cannot be combined with other environmental resource spatial data for analysis. This paper takes Chongqing as an example, selects nighttime light data etc. as variable factors affecting population distribution. Using the Xgboost model to build a regression model on the county level, and generates the population data of 100m in Chongqing in 2010. The accuracy of the population spatialization results and three public data sets were compared on the township scale. Finally, based on the importance of the variable factors of the Xgboost model, the influencing factors of the spatial distribution of Chongqing’s population were explored. The results show that the root mean square error in this paper is significantly better than the other three population data sets, the absolute value error is significantly better than the GPW data set and the Chinese kilometer grid data set, and slightly better than the World Pop data set. Through the analysis of the importance of variable factors, it is found that the distance from construction land is the most important indicator, and the nighttime light data, residential area and POI data all play an important role in population distribution of Chongqing.
Delineating the future boundaries of urban development using the FLUS Model: A Case Study of Zhaoyuan City, China
Authors: Wang Yizhan , Hu ZhengLiang , Zhang Yanming 
Published: June 2021

Abstract
Zhaoyuan City in Shandong Province, China was used as an example to explore the driving factors, constraints, and model parameterization using the FLUS-UGB model. Using observed data from 2018 to determine the model accuracy, the Kappa coefficient was found to be 0.8132, the overall accuracy was 0.8924, and the reliability was high. The forecast results show that, from 2018 to 2030, the urban land area growth rate of Zhaoyuan City was 11.40%, with the central and northwestern regions showing higher growth rates. The urban land area growth rate of Jinling Town was the highest at 42.53%, while Mengzhi and Wenquan Streets and Xinzhuang Town’s urban land area growth rate exceeded 10%. Other towns’ urban land area growth rate was less than 10%.
Application of Excel in Leveling and Traverse Survey
Authors: Wen Xumin , Guo Xiaozi 
Published: June 2021

Abstract
It mainly discusses the application of Excel in field leveling and traverse adjustment calculation in this thesis. Excel has powerful functions of formula editing and function, so we use it to process survey data. We realize the advantages of Excel software in the measurement data processing. It is convenient, flexible, simple, and clear. A good Excel calculation table can be used in future work. It only needs to adjust the original data without repeating the arrangement and design of calculation formulas. It can completely replace the programmable calculator and bring a lot of convenience to the work.
Design intervention process and intervention strategy of “Constant-holistic Shadow” space in hot summer area
Authors: Li Yinan , Gong Zhaoxian , Liu Yingqi , Luo Guohui 
Published: June 2021

Abstract
It is one of the goals of outdoor space design in hot summer areas to construct a “constant-holistic shadow” space for outdoor people that can always be in the shadow during the required period of time in summer. However, the relevance and process of design elements related to the space of “constant-holistic shadow” are different from those of conventional design, as well as methods, stages and objectives of design intervention. Therefore, it should be controlled according to appropriate stage design objectives and contents. Based on the relationship between the design goal and the design process of “constant-holistic shadow” space, this paper analyzed the feasibility of the design process intervention under the construction goal of “constant-holistic shadow” space and clarified the corresponding design intervention process and strategies. It is expected to provide green design ideas and methods for promoting the utilization efficiency of summer shadow and optimizing the thermal comfort of outdoor public space in summer hot areas, as well as enrich the relevant theories and methods of outdoor public space design.
Planning Strategy and Practice of Urban Wetland Park—A Case Study of Yuanbaozi Wetland Park
Authors: Shen Duwen , Li Yi , Zeng Yicheng 
Published: June 2021

Abstract
In the planning practice of Yuanbaozi Wetland Park in Zongzhai Town, Xi Ning City South New Area, planners insist on building five core functions with nature as the base and culture as the vein, so as to build a plateau city ecological wetland integrating ecological conservation, cultural experience, tourism distribution, popular science education and image promotion. They always put ecological protection in the first place, and each division combines landscape function with ecological protection, which provides a model for the planning practice of other urban wetland parks.
Existing Problems and Countermeasures of Energy-efficiency Residence Exploitation in China
Authors: Chen Boyang 
Published: June 2021

Abstract
Energy-efficiency residential building, based on the concept of green building, aims to solve the new field of residential problems. The purpose of the development of energy-efficiency residential buildings is to provide livable buildings for people with the lowest energy consumption. It reduces energy consumption throughout the life cycle of the building and contributes to sustainable development. However, this study finds that there are many obstacles in the process of promoting the use of energy-efficiency houses. There is not sufficient government support. Real estate companies avoid the promotion of energy-efficient buildings on a large scale by pursuing the maximization of profits. Buyers are blindly buying due to a lack of energy-saving awareness and related knowledge. To solve these problems, through literature research, this paper shows the progress status of the domestic energy-efficiency houses, excavated the existing obstacles, and attempt to offer specific measures and methods to break the obstacles from the three dimensions of government, enterprises and customers.