Abstract:
We construct a new family of minimal smooth surfaces of general type with K^2=7 and p_g= 0. We show that for a surface in this family, its canonical divisor is ample and its bicanonical morphism is birational. We prove that these surfaces satisfy Bloch's conjecture.

Abstract:
Let $S$ be a smooth minimal complex surface of general type with $p_g=0$ and $K^2=7$. We prove that any involution on $S$ is in the center of the automorphism group of $S$. As an application, we show that the automorphism group of an Inoue surface with $K^2=7$ is isomorphic to $\mathbb{Z}_2^2$ or $\mathbb{Z}_2 \times \mathbb{Z}_4$. We construct a $2$-dimensional family of Inoue surfaces with automorphism groups isomorphic to $\mathbb{Z}_2 \times \mathbb{Z}_4$.

Abstract:
The aim of this article is to classify the pairs (S, G), where S is a smooth minimal surface of general type with p_g=0 and K^2=7, G is a subgroup of the automorphism group of S and G is isomorphic to the group $\mathbb{Z}_2^2$. The Inoue surfaces with K^2=7, which are finite Galois $\mathbb{Z}_2^2$-covers of the 4-nodal cubic surface, are the first examples of such pairs. More recently, the author constructed a new family of such pairs. They are finite Galois $\mathbb{Z}_2^2$-covers of certain 6-nodal Del Pezzo surfaces of degree one. We prove that the base of the Kuranishi family of deformations of a surface in this family is smooth. We show that, in the Gieseker moduli space of canonical models of surfaces of general type, the subset corresponding to the surfaces in this family is an irreducible connected component, normal, unirational of dimension 3.

Abstract:
A novel channel representation for a two-hop decentralized wireless relay network (DWRN) is proposed, where the relays operate in a completely distributive fashion. The modeling paradigm applies an analogous approach to the description method for a double-directional multipath propagation channel, and takes into account the finite system spatial resolution and the extended relay listening/transmitting time. Specifically, the double-directional information azimuth spectrum (IAS) is formulated to provide a compact representation of information flows in a DWRN. The proposed channel representation is then analyzed from a geometrically-based statistical modeling perspective. Finally, we look into the problem of relay network tomography (RNT), which solves an inverse problem to infer the internal structure of a DWRN by using the instantaneous doubledirectional IAS recorded at multiple measuring nodes exterior to the relay region.

Abstract:
We completely classify canonically polarized smooth $3$-folds $X$ with $K_X^3=\frac{4}{3}p_g(X)-\frac {10}{3}$ and $p_g(X) \geq 7$. New examples of $3$-folds satisfying the properties above are constructed.

The
cointegration test, granger causality test, VAR model, impulse response
function and other econometric methods are used in this paper to analyze the
influencing effect between commercial housing vacancy rate and CPI and its
delay impact. The results show that there is a long-term equilibrium
relationship between commercial housing vacancy rate and CPI in China. There
are at least one cointegration relationship between CHVR and CPI. The past
values of the CPI appear to contain information which is useful for forecasting
changes in the CHVR. CPI has a significant effect on CHVR and CPI rising drives
CHVR.

Abstract:
This article discusses in detail chemical composition, molecular structure,
microstructure phenomena, estimate of the palaeo-stress, paleo-temperature
and the strain rate to deepen the knowledge for the correlation of coal deformation
and metamorphism with structural environment in Xinhua Hunan by
coal quality analysis, XRD and SEM methods, which provide dependable
theoretical foundation for coal resource exploitation and utilization. The results
show that 1) d002 value of six coal samples is from 3.36 to 3.39 nm, coal
resolved itself into aphanitic graphite with the increase of coal rank during
coalification, which is characterized by graphite flakes, and the crystallite size
is from 50 nm to 250 nm; A certain degree of 3R-structure content is increases
and the crystallite size is extend with the coalification process, but
RH-structure content is decreased; 2) the tectonic environment of research
area belongs to the ductile-brittle deformation, which was characterized by
low temperature, low stress, high strain rate; 3) Tianlongshan magmatic intrusion
provided heat source, its side-extrusion made the molecules structure
of coal ordering, distance between layers decreased, finally it caused the formation
of aphanitic graphite.

Abstract:
It has been shown that remote monitoring of pulmonary activity can be achieved using ultra-wideband (UWB) systems,which shows promise in home healthcare, rescue, and security applications. In this paper, we first present a multi-ray propagation model for UWB signal, which is traveling through the human thorax and is reflected on the air/dry-skin/fat/muscle interfaces. A geometry-based statistical channel model is then developed for simulating the reception of UWB signals in the indoor propagation environment. This model enables replication of time-varying multipath profiles due to the displacement of a human chest. Subsequently,a UWB distributed cognitive radar system (UWB-DCRS) is developed for the robust detection of chest cavity motion and the accurate estimation of respiration rate. The analytical framework can serve as a basis in the planning and evaluation of future measurement programs. We also provide a case study on how the antenna beamwidth affects the estimation of respiration rate based on the proposed propagation models and system architecture.

Abstract:
We introduce a realistic frequency-dependent channel model for ultra-wideband (UWB) communication systems and develop a generalized broadband Capon spatial spectrum estimator for localization of multiple incoherently distributed scattering clusters. The proposed estimator is able to address the three crucial features of practical UWB impulse propagation: presence of local scattering for multiple incoherently distributed clusters, wideband array signals, and frequency-dependent dispersive effects. The particle-swarm optimization, which is a recently invented high-performance optimizer based on the movement and intelligence of swarms, is then implemented to perform a multidimensional parameter search to jointly estimate the source central angles, the polynomial regression coefficients for angle spreads, and the frequency-dependence of various clusters. Numerical experiments are also carried out to examine the performance of the algorithm under various environments and model mismatches.

Abstract:
In recent years,
the global climate governance is not just for a global environmental problem of
climate change, more involved in international politics, economy, investment, technology
and other fields, and involves the transformation of production and life style.
Accompanied by global energy and technology revolution, the development of low carbon
is our inevitable requirement. Recently, China submitted to UNFCCC (United Nations
Framework Convention on Climate Change) the Secretariat of the national independent
contribution plan and set emission reduction targets: carbon dioxide emissions reach
the peak in 2030 and strive to reach the peak as early as possible; carbon emission
intensity decreased by 60% - 65% compared with that in 2005. This means that our government will intensify
its efforts to reduce carbon emissions. In the past, our target was to reduce
carbon emissions intensity, but now our country is to realize the reduction of
total carbon emissions, or “absolute reduction”. Carbon finance is an important
breakthrough in the development of low carbon economy and the promotion of carbon
emission reduction. This paper focuses on the analysis of the development status
of China’s carbon financial market, the problems and the opportunities and challenges
faced, and finally, the relevant countermeasures and suggestions are given from
the perspectives of policy, talent, mechanism, international cooperation and so
on, in order to promote the development of carbon financial market innovation, to
seize the commanding heights of the era of low-carbon economy.