738 research outputs found
The perils of credit booms
We present a dynamic general equilibrium model of production economies with adverse selection in the financial market to study the interaction between funding liquidity and market liquidity and its impact on business cycles. Entrepreneurs can take on short-term collateralized debt and trade long-term assets to finance investment. Funding liquidity can erode market liquidity. High funding liquidity discourages firms from selling their good long-term assets since these good assets have to subsidize lemons when there is information asymmetry. This can cause a liquidity dry-up in the market for long-term assets and even a market breakdown, resulting in a financial crisis. Multiple equilibria can coexist. Credit booms combined with changes in beliefs can cause equilibrium regime shifts, leading to an economic crisis or expansion.Published versio
Experimental study on deformation properties of unsaturated compacted soil based on digital image measurement
Due to the end restraint or the restraint of contact transducers to sample deformation, the results of conventional strain measurement method can not reflect the properties of sample deformation comprehensively. The digital image measurement method can measure the deformation of overall and local sample non-intrusively and selectively and can overcome some shortcomings of using conventional strain measurement method for unsaturated soil sample in suction-controlled triaxial tests. The deformation measurement results of unsaturated compacted soil samples show that the end restraint has significant effect on the deformation of the sample. The deformation properties of middle 1/3 sample are evidently different from those of the overall sample that is affected by the end restraint in suction-controlled isotropic loading and triaxial compression tests. The deformation measurement results of middle 1/3 sample can really correspondingly reflect basic deformation properties of unsaturated soil and study a constitutive model preferably
A Comparative Study of Thinking Quality Between Chinese and American Junior Middle School Students From the Perspective of Key Competences of English Subject
The globalization and information tide in the 21st century have promoted the new demand for talents in social development, and the key competences education came into being under such an era. Subsequently, the “key competences” became the key word of the global educational reform under the background of the new era in the 21st century. The key competences documents promulgated by many countries have obvious consistency and similarity, but they are not completely identical. There may be some problems worthy of reflection behind the differences. As the largest developing country and the largest developed country in the world, the educational views of China and the United States have a profound impact on the world civilization and pattern. As far as English subject is concerned, although English education is foreign language education in China, not native English education or non-native English education in the United States, it is combined with the reality of English education in China. Comparing the similarities and differences in the field of thinking quality between Chinese and American junior middle school English education can promote the reform of domestic English education and improve its quality. Also, many teachers only pay attention to the cultivation of students’ language knowledge and skills in the English classroom at present, neglecting the cultivation of students’ thinking quality, so it is difficult to improve students’ thinking ability and thinking personality traits. Based on this, the paper aims to cultivate and develop thinking quality of junior middle school students from the perspective of key competences of English subject. Through a comparative study of the consistency and difference of thinking quality between Chinese and American junior middle school students by using the methods of literature research and comparative analysis, the paper pays more attention to the problems of thinking quality of junior middle school students in China. As a result, the corresponding solutions are discussed. The paper is divided into five chapters. The first chapter is the introduction. The research background, research purposes, research significance, research problems and research methods are briefly described. The second chapter is the literature review. It covers the research status and research trend of thinking quality at home and abroad. The third chapter is comparative study. This part briefly introduces the framework of Chinese and American key competences, discusses in detail the consistency and differences of Chinese and American junior high school students’ thinking quality in the three dimensions of logic, criticism and innovation, and points out the similarities and differences. The fourth chapter explores the essence of differences. From the perspective of English curriculum, this paper explains the reasons for the differences in thinking quality between Chinese and American junior high school students, including classroom teaching, reading and writing. The fifth chapter is a reflection. It discusses the limitations of the cultivation of thinking quality of junior middle school students in China, draws lessons from useful experience, and initially explores the methods of cultivating thinking quality of junior middle school students, in order to enhance the comprehensive strength of the key competences of junior middle school students
A dynamic truck dispatching problem in marine container terminal
In this paper, a dynamic truck dispatching problem of a marine container terminal is described and discussed. In this problem, a few containers, encoded as work instructions, need to be transferred between yard blocks and vessels by a fleet of trucks. Both the yard blocks and the quay are equipped with cranes to support loading/unloading operations. In order to service more vessels, any unnecessary idle time between quay crane (QC) operations need to be minimised to speed up the container transfer process. Due to the unpredictable port situations that can affect routing plans and the short calculation time allowed to generate one, static solution methods are not suitable for this problem. In this paper, we introduce a new mathematical model that minimises both the QC makespan and the truck travelling time. Three dynamic heuristics are proposed and a genetic algorithm hyperheuristic (GAHH) under development is also described. Experiment results show promising capabilities the GAHH may offer
Using Video to Validate Vehicle Speed Uncertainty in Vertical Side Collisions
Vehicle speed access is an important part of road traffic accidents. Many factors affect the speed of the vehicle in vertical side collisions. Uncertainty in speed calculations related to vehicle collision was researched. The main parameters which have a greater impact on the speed of calculation results were discussed. And speed calculation methods based on uncertainty factors have been analyzed. By use of the vehicle vertical side collisions case, the speed of uncertainty has been carried out. Combined with accident surveillance video, the video picture computed speed and uncertainty factors obtained speed were compared. The results showed that selected road adhesion coefficient, vehicle weight and other parameters as the uncertainty factors, the use of uncertainty obtained speed with high reliability of forensic, which can be used in accident reconstruction
Efficient Frequency Domain-based Transformers for High-Quality Image Deblurring
We present an effective and efficient method that explores the properties of
Transformers in the frequency domain for high-quality image deblurring. Our
method is motivated by the convolution theorem that the correlation or
convolution of two signals in the spatial domain is equivalent to an
element-wise product of them in the frequency domain. This inspires us to
develop an efficient frequency domain-based self-attention solver (FSAS) to
estimate the scaled dot-product attention by an element-wise product operation
instead of the matrix multiplication in the spatial domain. In addition, we
note that simply using the naive feed-forward network (FFN) in Transformers
does not generate good deblurred results. To overcome this problem, we propose
a simple yet effective discriminative frequency domain-based FFN (DFFN), where
we introduce a gated mechanism in the FFN based on the Joint Photographic
Experts Group (JPEG) compression algorithm to discriminatively determine which
low- and high-frequency information of the features should be preserved for
latent clear image restoration. We formulate the proposed FSAS and DFFN into an
asymmetrical network based on an encoder and decoder architecture, where the
FSAS is only used in the decoder module for better image deblurring.
Experimental results show that the proposed method performs favorably against
the state-of-the-art approaches. Code will be available at
\url{https://github.com/kkkls/FFTformer}.Comment: Code will be available at \url{https://github.com/kkkls/FFTformer
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